We have a phrase. If we don't know where we come from, we don't know where we go.

In Spanish, if we don't know where we come from, we don't know where we go.

We're in the historic center of Mexico's capital, Mexico City, a massive city of over 8 million people.

With tour guide Ismail Rivera.

Hola, buenas tardes. My name is Ismail Rivera. I was born in Mexico City.

I can't help but go on a historic tour of pretty much everywhere I visit now.

Underneath here there's three Aztec temples dedicated to the sun, to the wind,

Ismail guides us through winding streets past towering Gothic churches, ancient Aztec temple sites,

or neatly engraved Spanish colonial arches, a salsa class in one square,

and a busy market with taco vendors every two feet.

The smell is delicious, like unreal.

And then we find ourselves in a quieter place, surrounded by tall trees,

fountains with statues of Greek gods, and these vibrant purple flowers called Hacarandas.

This is a la meta part. It was the first one in American continent.

A la meta central park was built in the 16th century. It sits right off of Cinco de Mayo Avenue.

And Diego Rivera paints a mural about this park.

Diego Rivera, who's considered one of the greatest Mexican painters of the 20th century,

called this mural, suenio de un atarde dominical en la Alameza Central,

dream of a Sunday afternoon in Alameza Central.

A replica of the mural stretches maybe 50 feet long across the side of a building at one end of the park.

Is it either the different periods, the Spanish period, colonial period?

The mural basically tells the entire history of Mexico from the fall of the Aztec Empire in the 16th century,

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