The Rio Lerma (Chignahuapan) in El Salto, Mexico, is one of the most polluted rivers in the world. It’s covered in white foam, and falling in can kill.

The masses at this church incorporate enough moonshine and animal sacrifice that they are no longer recognizably Catholic.

This giant expressionist head crowns a museum devoted to a beloved Mexican leader.

Huge hole looks down onto an underground beach populated with sea lions.

Mexico's first public cable car soars over the congested streets outside Mexico City.

The "world's smallest volcano" has been used to store meals and dispose of dead bodies.

This ceremonial Mexican square looks as though it belongs in a science fiction movie.

A Lovecraftian altar of nightmarish bronze chairs sits ominously on a boardwalk in Puerto Vallarta.

Stained glass windows bathe this botanical garden in cosmic light.

The stoutest tree in the world.

Clap your hands at the base of the pyramid, and the song of a sacred Mayan bird will echo through the air.

A museum in the former home of Marxist revolutionary Leon Trotsky.

Meant to be one of the most extravagant hotels in the world, now an eerie, abandoned architectural gem in Mexico City.

The meteor that sealed the fate of the dinosaurs landed at this site, one of the largest impact craters in the world.

A dark tunnel leads to a striking white crater that seems to be from another planet.

The jewel of western Mexico's archaeological legacy is this tiered circular pyramid now covered in grass.

This beautifully deceptive waterfall is something far different from what it appears to be.

The famous artist couple lived and worked here, in two different houses separated by a bridge.

The winter home of millions of migrating monarch butterflies.

The splendor of this 17th century golden chapel has led it to be called the "eighth wonder of the world."

The ruins of an ancient Mayan city, beautifully preserved and only accessible by boat.

Two waterfalls flow down the cliff faces decorated with rare natural basalt columns.

An ancient system of freshwater caves filled with animal bones, including that of species long-extinct.

A 500-year-old series of tunnels long believed to be folkloric was uncovered beneath the streets of Puebla.