A Travel Price Comparison for Families, Couples, and Backpackers Mexico City vs. San Diego for Attractions, Food, Nightlife, and Families

Should you visit Mexico City or San Diego?

Which is cheaper to visit? Which is more expensive for vacation?

Should I visit Mexico City or San Diego? This is a common question asked by many travelers. By figuring out which city has activities that align with your interests along with knowing which is more affordable, you'll understand where you can get more bang for your buck. So, let's dive into the details and the data, which all comes from actual travelers.

Mexico City

Mexico City is a cultural, diverse, and vibrant city. With plenty of activities and things to do, it's a huge city that draws plenty of visitors. Visitors also love the museums, nightlife, and food. See Mexico City travel costs.

San Diego

San Diego is a outdoorsy, idyllic, and fun-filled coastal city. Because this is such a big city, visitors will find many sights and attractions around town. San Diego offers plenty of beauty for visitors. As this is a very quaint destination, you'll find it has a special atmosphere. It's also popular because of the hiking, shopping, and museums. See San Diego travel costs.

Mexico City and San Diego: Pros and Cons

Pros
  • Popular museums and historical sights
  • Active nightlife
  • Scenic old town
  • Fun shopping
  • Family-friendly
  • Good for backpackers and budget travelers
  • Good public transit
  • Big city activities
Things to Consider
  • Less popular with couples
Pros
  • Popular museums and historical sights
  • Active nightlife
  • Good music scene
  • Nice resorts
  • Good scuba and snorkeling destination
  • Popular beach
  • Good for hiking
  • Known for its beauty
  • Family-friendly
  • Good for couples and romance
  • Good for backpackers and budget travelers
Things to Consider
  • Less popular for shopping
  • Public transit not as usable


Is there more to do in Mexico City or San Diego?

Visitors will generally find more to do in San Diego than Mexico City. While Mexico City is larger than San Diego, San Diego has more sights, attractions, and activities for tourists. San Diego is more popular for its music, resorts, scuba diving & snorkeling, beaches, hiking, impressive beauty, and quaint atmosphere, while Mexico City is known for its museums and attractions, food, nightlife, historical sights, shopping, and big city activities. San Diego is more touristy than Mexico City and is known for its relaxed coastal atmosphere, its many kid-friendly sights, and its beautiful beaches with critter-filled tidal pools. It is also home to The San Diego Zoo. Mexico City is popular for its vibrant street food scene, colorful markets, and historic architecture.

How is Mexico City different from San Diego?

Which is Better for a Holiday?

Let's take a look at the differences and similarities between San Diego and Mexico City. Then, you can decide for yourself which place is better for your next trip.

Are the Museums and Historical Sights Better in Mexico City or San Diego?

Mexico City
San Diego

Mexico City is renowned for its historical sights. Also, San Diego is not as popular, but is still a nice coastal city for its sights and museums.

The museums and tourist attractions in Mexico City are world-renowned. The city is filled with historic buildings, fascinating museums, and interesting landmarks. At the heart of the city is Zócalo, where the country's constitution was signed. Nearby you'll find the National Palace, the Metropolitan Cathedral, and the Templo Mayor. Other interesting museums in the city include the National Museum of Anthropology, the Palace of Fine Arts, and the National History Museum.

San Diego offers many unique museums, sights, and landmarks that will make for a memorable trip. While the city is famous for it's beaches, zoos, and aquariums, don't overlook the museums and other landmarks. Popular options include the Midway Aircraft Carrier Museum, the Old Town State Historic Park, and Point Loma and Cabrillo Monument.


Is the Food Better in Mexico City or San Diego? Which Destination has the Best Restaurants?

Mexico City
San Diego

Mexico City is renowned for its local flavors and cuisine. Also, San Diego is not as popular, but is still a nice coastal city for its local cuisine and restaurants.

Eat your way through Mexico City, as it has many local or world renowned restaurants to choose from. The city food scene is as diverse as the population itself. There are countless ways to experience the amazing street food, but there are also world class chefs working in award winning restaurants. Make sure you try the chilaquiles, tacos al pastor, and chiles en nogada.

Dining out in San Diego is an experience not to be missed. The city has great seafood and a diversity of cuisines. There are many casual dining options that serve informal foods like burgers or salads, but there are also award-winning fine dining restaurants with elegant atmospheres. Popular local dishes include fish tacos and California burritos.

Is Mexico City or San Diego Better for Nightlife?

Mexico City
San Diego

Mexico City is renowned for nightlife and partying. Also, San Diego is not as popular, but is still a nice coastal city for its evening party scene.

Mexico City is a destination that you simply have to visit at least once for nightlife. It's a huge city, so of course there's no shortage of diverse nightlife activities. Some of the most popular neighborhoods for nightlife include the downtown, La Condesa, and Colonia Juárez. For upscale clubs head to Polanco and for trendy and eclectic venues check out Roma.

San Diego has plenty to do after the sun goes down. The heart of the city's nightlife scene is in the Gaslamp District, which is filled with bars, clubs, and music venues. There's a young student population that keeps the nightlife scene casual and fun.

Is Mexico City or San Diego Better for Music?

Mexico City
San Diego

San Diego is an excellent place to visit for its music scene. However, Mexico City is not a live music destination.

Whether you like big venues or smaller artists, San Diego has diverse options. Popular venues include the House of Blues, The Belly Up, and The Shout House.

Mexico City is not a live music destination.


Is Mexico City or San Diego Better for Resorts?

Mexico City
San Diego

San Diego is a popular place for its luxury resorts. However, Mexico City is not a resort destination.

San Diego has a few great resort options. Most people prefer to stay in hotels or VRBOs, but several popular resorts include Fairmont Grand Del Mar, Paradise Point, and the famous Hotel del Coronado.

Mexico City is not a resort destination.

Is Mexico City or San Diego Better for Scuba Diving and Snorkeling?

Mexico City
San Diego

San Diego is a popular place for snorkeling and scuba diving. However, Mexico City is not a scuba or snorkeling destination.

San Diego has a few good snorkeling spots. Popular snorkeling and diving spots include La Jolla Cove, Mission Bay, and Turtle Town. The water's a bit chili, but it's still worth going for a dive or popping on a mask and snorkeling around for a bit.

Mexico City is not a scuba or snorkeling destination.

Is Mexico City or San Diego Better for Beaches?

Mexico City
San Diego

San Diego is very popular for the beach. However, Mexico City is not a beach destination.

Travelers come from around the world to visit the beaches in San Diego. The city has great beaches with tidal pools and interesting sea life at low tide. Adults and kids alike will enjoy hitting the beach when the tides are out and looking for local critters in the tidal pools. Popular beaches in the area include La Jolla Cove Beach, Coronado Beach, and Pacific Beach.

Mexico City is not a beach destination.


Is Mexico City or San Diego Better for its Old Town?

Mexico City
San Diego

Mexico City is a good destination for its old town. However, San Diego does not have a historic old town.

Plenty of visitors enjoy exploring the old town in Mexico City. Centro Historico spreads out from Zócalo Plaza, and has many buildings that date back as far as the Aztec period. Many tourists gather here to explore the history and wander down the pedestrian-only Calle Madero.

San Diego does not have a historic old town.

Is Mexico City or San Diego Better for Hiking?

Mexico City
San Diego

San Diego is an excellent place to visit for its hiking trails. However, Mexico City is not a hiking destination.

Many visitors explore the nearby hiking trails while visiting San Diego. The city is filled with parks and has tons of natural beauty. There is plenty of urban hiking in town, or you can visit more natural areas just out of town. Head to Torrey Pines State Park or Los Penasquitos Canyon Trail for some nice hikes.

Mexico City is not a hiking destination.

Is the Shopping Better in Mexico City or San Diego?

Mexico City
San Diego

Mexico City is renowned for its shopping opportunities. Also, San Diego is not as popular, but is still a nice coastal city for its shopping areas.

Known for shopping, Mexico City draws large crowds to its stores. The city has everything from open-air bazaars (tianguis) to modern shopping malls. There are international brands as well as local art galleries, handicrafts, and retail outlets.

Many visitors go to San Diego to go shopping. Head to Fashion Valley or Westfield UTC for some fun shopping. There are suburban shopping malls in the area as well as souvenir shops in the more touristy areas.


Is Mexico City or San Diego More Beautiful?

Mexico City
San Diego

San Diego is a popular place for its scenery and beauty. However, Mexico City is not a destination known for its beauty.

San Diego offers plenty of beauty for visitors. Many people enjoy city's beautiful coastline and surrounding natural beauty.

Mexico City is not a destination known for its beauty.

Is Mexico City or San Diego Better for Families?

Mexico City
San Diego

San Diego is very popular for its kid-friendly activities. Also, Mexico City is not quite as popular, but is fairly good for its family-friendly activities.

As it has a large number of activities for kids, San Diego is a very family-friendly destination. The city is filled with kid-friendly activities that everyone can enjoy. There's the world-class zoo, several amusement parks, the beaches, aquariums, and more. The year-round warm weather makes it easy to spend plenty of time outdoors in parks, playgrounds, and beaches where kids can stretch their legs and run around.

Mexico City is a very family-friendly place to visit. It's a huge city, so there are enough diverse activities to keep everyone entertained. There's even a Six Flags. Popular museums for kids include Papalote Museo del Niño and Museo de Geología. There's also the Acuario Inbursa, and make sure you check out a Lucha Libre show.

Is Mexico City or San Diego Better for Couples?

Mexico City
San Diego

San Diego is very popular for couples. Also, Mexico City is not quite as popular, but is fairly good for romance.

San Diego makes for a terrific place to visit as a couple. For adventurous couples, there are many outdoor activities that you can enjoy together. The beaches offer a great playground for adults who enjoy the water and warm weather. There are also restaurants and a great nightlife in San Diego.

Mexico City is a nice destination for couples. The city is filled with parks where you can enjoy a picnic, museums that are fascinating to walk through, and cultural activities that are one-of-a-kind. You can ride on a gondola in Xochimilco or spend the day exploring the amazing food scene.


Is Mexico City or San Diego Better for Backpackers and Budget Travelers?

Mexico City
San Diego

Mexico City is great for backpackers and budget travelers. Also, San Diego is not as popular, but is still a nice coastal city for backpackers.

Many backpackers visit Mexico City. It's a big city with a wonderful atmosphere and many hostels. Backpackers who want to experience the culture, food, and personality of Mexico will love a visit here.

Plenty of budget travelers visit San Diego. Backpackers will enjoy the young vibe of the city. There are a few great hostels near the beach or in town.

Is Mexico City or San Diego Better for Students?

Mexico City
San Diego

San Diego is very popular for its student-friendly activities. Also, Mexico City is not quite as popular, but is fairly good for students.

Many students frequent San Diego. With its young population and many universities, international students will feel right at home in San Diego. There are also many great outdoor activities for the adventurous.

Mexico City is very popular with students. International students love the art, architecture, food, and culture that this colorful city has to offer.

Is Mexico City or San Diego Better for Public Transit? Which Is Easier to Get Around Without a Car?

Mexico City
San Diego

Mexico City is great for times when you don't have a car. However, San Diego is not a good destination for its public transit.

The public transit in Mexico City can get you around easily. The city has a complex and comprehensive public transit system that includes a metro, metrobus, and local buses.

Public transit is generally limited in San Diego. The city has a trolley (light rail system) as well as a bus system. Most people depend on cars to get around, and you'll likely enjoy your trip a bit more if you have your own vehicle.


Is Mexico City or San Diego a more walkable city?

Mexico City
San Diego

San Diego is a popular place for its ease of walking around. However, Mexico City is lacking in options for its walkability.

San Diego is a somewhat walkable coastal city. The downtown area is walkable, but if you want to travel further, you'll need to find a different form of transportation.

Mexico City is generally not very walkable. While you can walk within many neighborhoods, such as the historic city center, it's impossible to walk between neighborhoods and in many parts of the city.

For even more information, also check out Is Mexico City Worth Visiting? and Is San Diego Worth Visiting?.

Should I spend more time in San Diego or Mexico City?

How long in Mexico City or San Diego?

In either Mexico City or San Diego, you'll find plenty of activities to fill your time. In our opinion, San Diego has more to see and do, so we recommend spending more time in San Diego than Mexico City. However, 3-5 days is a good amount of time to spend in either destination.

Families should spend more time in San Diego than Mexico City. Because of the many family-friendly attractions and fun things to do for kids in San Diego, it's a great place to visit with the whole family.

Couples should spend more time in San Diego than Mexico City. You'll find plenty of romantic sights and fun activities in San Diego that are perfect for a weekend getaway or a longer couple's trip.

Backpackers and budget travelers should spend more time in Mexico City than San Diego if your budget allows for it. With a larger number of budget-friendly sights, good nightlife, and active things to do, anyone traveling on a budget would have a good time in Mexico City.


  • How many days in Mexico City or San Diego? Ideal Length of Stay
    Mexico City 3-5 
    San Diego 3-5

One day in Mexico City or San Diego?

People visit Mexico City because there is so much to do. Since there is so much to do in the area, one day is probably not enough for all of it. It has many unique tourist attractions and fascinating things to do.

Visitors enjoy the nightlife and live music when visiting the fun-filled coastal city of San Diego. It's also a great beach destination, too. Most people visit for the beaches. One day is usually not enough time for a trip here as there is plenty to do. The entire region has so many activities, and you'll want time to do everything.

A weekend in Mexico City or San Diego?

People visit Mexico City because there is so much to do. A weekend is usually not enough time for a trip here as there is plenty to do. This city offers a variety of activities to choose from.

Visitors enjoy the live music and food when visiting the fun-filled destination of San Diego. Many visitors also spend a good bit of time hiking. This coastal city offers something for everyone. Since there is so much to do in the area, a weekend is probably not enough for all of it.


Five days in Mexico City or San Diego?

People visit Mexico City because there is so much to do. The length of your ideal trip is an individual decision. If you have five days, this city makes for a great vacation. Five days should give you a good understanding of everything this city has to offer.

Visitors enjoy the food and scuba diving and snorkeling when visiting the relaxed coastal city of San Diego. You'll find plenty of activities on the beach. Many people spend five days here.If you enjoy all that's offered here, then five days is just the right amount of time to spend here. The length of your trip often depends on your style of travel.

A week in Mexico City or San Diego?

Mexico City is a popular choice for travelers. One week is usually plenty of time to spend here with extra days to spare. With this much time, visitors often visit nearby destinations or take day trips. It will give you the chance to have new experiences.

Many people enjoy the scuba diving and snorkeling and shopping when visiting San Diego. Anyone can find something fun to do here. Most people come for the beaches. Most people visit for the beaches. Most people find that one week is more than enough time to see everything.


For some great organized tour ideas, see The Best 2-Week Tours in Mexico, Tours for Outdoor and Nature Lovers in Mexico, The Best G Adventures Tours to United States of America, and The Best One-Week (7-Day) Tours from Las Vegas.


Which place is cheaper, San Diego or Mexico City?

These are the overall average travel costs for the two destinations. These travel costs come from the actual spending of real travelers.

  • Mexico City Prices
    Mexico Prices
    San Diego Prices
    USA Prices
  • Average Daily Cost Per person, per day
    Mexico City $212
    San Diego $233

The average daily cost (per person) in Mexico City is $212, while the average daily cost in San Diego is $233. These costs include accommodation (assuming double occupancy, so the traveler is sharing the room), food, transportation, and entertainment. While every person is different, these costs are an average of past travelers in each destination. What follows is a categorical breakdown of travel costs for Mexico City and San Diego in more detail.



Accommodation
  • Accommodation Hotel or hostel for one person
    Mexico City $38
    San Diego $115
  • Accommodation Typical double-occupancy room
    Mexico City $76
    San Diego $230
Compare Hotels in Mexico City and San Diego

Looking for a hotel in Mexico City or San Diego? Prices vary by location, date, season, and the level of luxury. See below for options and compare which is best for your budget and travel style.

Hotels in Mexico City


Hotels in San Diego


Kayak helps you find the best prices for hotels, flights, and rental cars for destinations around the world. Compare prices for multiple destinations when planning your next trip.


Our Analysis
We've analyzed the average and typical hotel prices based on guest reviews, star ratings, and hotel amenities here: Mexico City Hotel Prices and San Diego Hotel Prices.

Local Transportation
  • Local Transportation Taxis, local buses, subway, etc.
    Mexico City $12
    San Diego $23
Typical Local Transportation Prices in Mexico City

Here are some examples of typical transportation prices from actual travelers in Mexico City:


  • Metro
    $1.09
  • Uber Ride
    $3.80

Hired Cars and Shuttles in Mexico City

Also for Mexico City, here are a few examples of actual transportation services:

  • Mexico Airport (MEX) Tecozautla - Round-Trip Private Transfer: $252
  • Transfer from Mexico City Airport to Puebla: $245
  • Private Balloon Flight Over Teotihuacan with Optional Transfer: $243
  • Mexico Airport(MEX) to Chignahuapan - Round-Trip Private Transfer: $236
  • Mexico City Private Transfer to or from Airport: $216
  • Airport Transfer: Mexico Airport NLU to Mexico by Luxury SUV: $214
  • Airport Transfer: Mexico to Mexico Airport NLU by Luxury SUV: $203
  • Private Transfer from Mexico City to Pachuca: $192
  • Private Transfer from Pachuca to Mexico City: $192
  • Private Departure Transfer from Toluca City hotels to Toluca airport: $174
  • San Miguel De Allende City Tour with Transfer from Mexico City: $156
  • Tecozautla to Mexico City Airport (MEX) - Departure Transfer: $126

Hired Cars and Shuttles in San Diego

Also for San Diego, here are a few examples of actual transportation services:

  • Tijuana to Tijuana International Airport (TIJ) - Round-Trip Private Transfer: $141
  • Tijuana to Tijuana International Airport (TIJ) – Departure Private Transfer: $71
  • Tijuana Intl Airport (TIJ) to Playas de Rosarito - Arrival Private Transfer: $277
  • Tijuana International Airport (TIJ) to Tijuana hotels - Arrival Private Transfer: $71
  • Sedan Departure Transfer San Diego to San Diego Airport SAN: $104
  • Sedan Arrival Private Transfer San Diego Airport SAN to San Diego: $125
  • San Marcos, CA to San Diego Airport (SAN) - Departure Private Transfer: $66
  • San Diego Airport (SAN) to San Marcos, CA - Arrival Private Transfer: $66
  • San Diego Airport (SAN) to Hot Springs/Ocotillo, CA - Arrival Private Transfer: $66
  • Roundtrip Private Transfer from Tijuana Airport (TIJ): $77
  • Private Transfer to Tijuana Airport (TIJ): $39
  • Private Transfer to San Diego International Airport from San Diego: $77

Is it cheaper to fly into Mexico City or San Diego?

Prices for flights to both San Diego and Mexico City change regularly based on dates and travel demand. We suggest you find the best prices for your next trip on Kayak, because you can compare the cost of flights across multiple airlines for your prefered dates.





Food
  • Food Meals for one day
    Mexico City $43
    San Diego $77
Typical Food Prices in Mexico City

For Mexico City, here are some examples of average food and meal prices for travelers:


  • Lunch for Two
    $12
  • Coffee and Snacks
    $4.24
  • Dinner for 2
    $25

Food Tours and Cooking Classes in Mexico City

For Mexico City, here are some samples of tours and activities related to meals and dining experiences:

  • Private Street Food Tour Mexico City - Best rated : $35
  • Veracruz and Boca del Rio Food Tour with Mangroves Boat Trip: $50
  • Virtual Mexican Cooking Class (private and personalized): $50
  • Coyoacán Market Food Tour Urban Eats & Local Legends: $52
  • San Juan Market Food Tour Exotic Bites & Flavors: $52
  • Tortilla Crawl: Food Tour in Mexico City: $55
  • Private Half-Day Traditional Markets Street Food Tour in Mexico City: $57
  • 3 Hours Food Tour Best Vegan Tacos in Mexico City: $61
  • Street Food Tour with Friends: $75
  • Mexico City Food Tour in the Historic Center: Heritage on a Plate: $77
  • MEXICO CITY FOOD TOUR: flavors on two wheels: $78
  • Flamenco Live Show and Dinner in Mexico City: $83

Typical Food Prices in San Diego

Here are some examples of typical meal expenses from previous travelers to San Diego:


  • Mexican Lunch for Two
    $27
  • Breakfast at Starbucks
    $20

Food Tours and Cooking Classes in San Diego

For San Diego, here are some samples of tours and activities related to meals and dining experiences:

  • 2 Hour Ravioli Cooking Class With Local Chef in San Diego : $75
  • North Park San Diego Walking Food Tour: $85
  • Little Italy Food and Drink Walking Tour: Pizza, Pasta & Piazzas: $90
  • San Diego Gaslamp Food Tour with 6 Modern Californian Tastings: $95
  • Gaslamp Quarter Downtown San Diego Food Tour: $99
  • City Cruises Buffet Dinner Cruise: $110
  • Walking food tour + Round trip ferry to Coronado Island : $125
  • San Diego Harbor Dinner Cruise: $126
  • City Cruises Gourmet Dinner Cruise & Skyline Views: $151
  • Private Cooking Demonstration of Indian Fusion Cuisine in San Diego: $228

Entertainment
  • Entertainment Entrance tickets, shows, etc.
    Mexico City $14
    San Diego $48

Tours and Activities in Mexico City

For Mexico City, here are a few prices for actual activities, tours, and tickets provided by various companies:

  • Frida Kahlo Tour with Admission Tickets: $76
  • Hiking Tour on the Iztaccíhuatl Volcano from Puebla (private): $176
  • Mexico City Tour and Visit Chapultepec Castle. Private service: $180
  • Private Tour Teotihuacan Essentials: $140
  • Private Walking Tour Gems of the Historic Center of Mexico City: $131
  • Private guided tour of the Soumaya Museum : $279
  • Romantic tour in San Andrés Mixquic: $150
  • Sunrise HotAir Balloon Adventure Over Teotihuacan's Pyramids: $160
  • Xochimilco Floating Gardens and Coyoacan Private Tour: $162
  • "Guided Tour Plus" EN Ruins "TEMPLE MAJOR" with OFFICIAL GUIDES: $34
  • 1 Day Tour to Zacatlán and Chignahuapan from Mexico city: $200
  • 1 day in Puebla and Cholula in private tour from Mexico city: $130

Typical Entertainment Prices in San Diego

For San Diego, here are some examples of average entertainment and activity prices from previous travelers:


  • San Diego Zoo
    $15
  • Sea World Parking
    $12

Tours and Activities in San Diego

Also, here are some specific examples of entertainment, tickets, and activities for San Diego.

  • Gaslamp Quarter to Little Italy Tour: $39
  • Maritime Museum of San Diego Admission Ticket: $28
  • Old Town Walking Tour: $129
  • The La Jolla Walking Tour: $119
  • The Little Italy Walking Tour: $99
  • 1 Hour GPS Guided Scooter Tour: Harbor/Gaslamp Quarter: $92
  • 1-Hour Private Scenic Tandem Sidecar Tour in San Diego: $99
  • 1.5 Hour Walking Tour from La Jolla in San Diego: $59
  • 2-Hour Downtown and Balboa Tour in GPS Guided Vanderhall GoCar: $288
  • 2-Hour GoCar Tour of Downtown San Diego and Old Town: $52
  • 2-Hour GoCar Tour of Downtown and Balboa Park: $90
  • 2-Hour San Diego Pier Fishing Experience: $75

Alcohol
  • Alcohol Drinks for one day
    Mexico City $19
    San Diego $21

Sample the Local Flavors in Mexico City

Here are a few nightlife and alcohol tours and activities from local tour providers in Mexico City:

  • Mexico City Pub Crawl: $23
  • Cavas Freixenet Wine Tour from Mexico City: $222

Sample the Local Flavors in San Diego

Also in San Diego, these are the prices for nightlife and alcohol related activities from various tour providers:

  • Self-Guided Scavenger Hunt: Slammin' San Diego Bar Crawl: $13
  • Hillcrest: LGBTQ+ Pub Crawl with Local Drag Queen: $35
  • $99 Valle de Guadalupe Wine Tours - DayTrip to baja from San Diego: $123
  • Cruise & Booze Brewery tours : $149
  • Baja Tour Guide wine tour: $169
  • Valle de Guadalupe Wine Tour: $249
  • Luxury Private Wine Tasting Tour to Guadalupe Valley from San Diego: $269


When comparing the travel costs between Mexico City and San Diego, we can see that San Diego is more expensive. However, the two cities are actually relatively comparable in price, as the difference is somewhat minimal. Generally, this means that you could travel with generally the same travel style and level of luxury in each place. Since both cities are in North America, it's no surprise that their costs are relatively close, as many destinations here have somewhat similar travel prices overall.

If you're trying to decide if either of these two destinations are within your price range, also see Is Mexico City Expensive? and Is San Diego Expensive?.


Which is Bigger, Mexico City or San Diego?

Mexico City has a larger population, and is about 9 times larger than the population of San Diego. When comparing the sizes of Mexico City and San Diego, keep in mind that a larger population does not always imply the destination has more attractions or better activities. So, always research the type of place that you want to visit along with the activities and attractions that interest you.