Diego Rivera's massive tiled fountain and failed infrastructure project.

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

Twelve natural mummies are displayed in the crypt of this former monastery school.

This fantastical house shaped like a seashell brings aquatic design to architecture.

A church dedicated to the Mexican skeleton saint.

A jaw-dropping "megalibrary" that turns book-browsing into a geometric adventure.

66,000 pieces of art, donated by one of the world's richest men.

No telescopes, no power, no gift shop: The Observatory of Chichen Itza, one of the world's oldest observatories, takes astronomy back to basics.

Every equinox this Maya pyramid puts on a spooky ancient light show.

An island filled with hundreds of hanging, decomposing, decapitated dolls.