Perched about 7,300 feet above sea level near the center of its home country, Mexico City is one of the most interesting and unique cities on the planet. Its history spans over seven centuries, and its construction is a marvel of engineering. And despite being a mega-city with tens of millions of residents, there are still some surprises hidden among its picturesque streets. Check out these six surprising facts that you may not have known about Mexico City.

It’s Among the Oldest Cities In the Americas

Aerial view of the Old Basilica of Guadalupe during the day with Mexico City skyline in background
Credit: Jess Kraft / Shutterstock

Numerous indigenous groups have lived in the area since 100 CE, but it wasn’t until 1325 that one of them decided to put down permanent roots. The Aztecs believed that the gods would show them where to build their great city by giving them a very specific sign: an eagle eating a snake on top of a cactus. They finally saw that exact sign on an island in the middle of Lake Texcoco. That was where they had to build their city. Originally, the city was named Tenochtitlan. When the Spaniards conquered the Aztecs in the 1500s, they built upon the ruins of Tenochtitlan and called their new city Mexico City.

In its expansive 700-year history, Mexico City changed hands several times, but it never stopped growing. You can still see the history throughout this thriving metropolis. Some of the streets and parks that people enjoy today date back to the time of the Aztecs in the 1300s.

It’s Built on a Lake

Aerial view of water reservoir in Mexico City with mountains in background
Credit: Ulrike Stein / Shutterstock

Once they saw the sign from the gods, the Aztecs began dumping soil into the lake to form an artificial island on which to build their city. The city continued to grow, bucket by bucket, until it was the largest and most powerful city in the pre-colonial world.

As it continued to grow, the lake got smaller and smaller until it was completely drained to make way for even greater expansion. Large reserves of water remained underneath the city from the ancient lake bed, almost like the city was resting on a giant waterbed. These reserves were used for drinking water to support the ever-growing population. As the water from the “waterbed” was used up, the city began to sink. It continues to sink at an average of 3.2 feet per year!

It Has a Huge Population

Street view of a crowded avenue in Mexico City on a bright afternoon
Credit: Alex Cimbal / Shutterstock

Mexico City has always been large. Even at its beginning, it was one of the largest and most powerful cities in the world. Today it has the fifth largest population in the world with over 21 million residents. It also has the largest population of U.S. citizens living outside the United States. More than 700,000 Americans call it home.

With such a massive population, Mexico City needs a huge infrastructure to support all those people. It has the largest airport and subway in Latin America, along with the greatest number of taxis of any city in the world. In fact, its metro system is one of the cheapest at only $0.27 per trip. With so many residents, traffic jams are a common problem, and many of the city’s wealthiest residents have resorted to using private helicopters to get around.

It’s an Economic Powerhouse

Water fountains in wealthy area of Park Parque in Mexico City with sunset in background
Credit: Suriel Ramzal / Shutterstock

Not only is Mexico City the largest city in Mexico, it also produces more than 20% of the GDP of the entire country. It houses the Mexican stock exchange and several of the largest banks in Latin America. If you think Mexico City has a powerful economy now, just wait a few years. The city’s economy is growing at a rate of almost 100 percent.

It Features One of the Largest Universities

The Central Library building with mural at the National Autonomous University of Mexico in Mexico City
Credit: bmszealand / Shutterstock

The National Autonomous University of Mexico (UNAM) was founded in 1551 and is one of the largest and oldest schools in the world with more than 340,000 students enrolled annually. The massive campus covers 2,500 acres of land and has many of the amenities that you would find in any full-sized city:

  • 26 museums
  • Olympic stadium
  • Ecological reserve
  • Botanical garden
  • Two fire stations

The top 10 floors of the UNAM library are covered with a beautiful mosaic to showcase the city’s long history. For its social and cultural significance, the library has been named a UNESCO World Heritage Site.

It’s a City of Palaces

Aerial view of the Palace of Fine Arts during the day in Mexico City
Credit: Kamira / Shutterstock

Countless dignitaries and wealthy colonial figures have called Mexico City home over the years. Many of them have left their mark by building elaborate palaces. There are so many palaces that the city has earned the nickname “The City of Palaces.” Most of the palaces that remain today have been turned into museums that are open to the public.

In 1725, the viceroy of the Spanish army decided that even a palace wasn’t good enough for a man of his status, so he constructed the Chapultepec Castle. In 1864 the castle became the home of the first, and only, Mexican Emperor. Today, the castle is not home to anyone but has been transformed into the National Museum of Culture and is open to the public.