A burial vault located under Tiber Island in the middle of the Italian capital.

Jesus' footprints and the first catacombs in the world.

This beautiful park on the outskirts of Rome protects the ruins of two colossal ancient aqueducts.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

A hospital where antique dolls are given new life.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

Detailed facade of a brownstone in Boerum Hill.

Unlock the secrets of the conjuring arts.

Great place to have a drink and a bite to eat in an atmosphere laden with New York's Bohemian past.

In Coyoacán, a pair of coyotes crown a public fountain in reference to the ancient Aztec name of the borough.

This ancient jade mask depicting the Zapotec bat god was found in the ruins of the pyramids of Monte Alban.

A scientific repository of goiters, boils and other ailments throughout Mexican history.

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

These subterranean models show Mexico City's central square during three different eras.

Diego Rivera hid various people and symbols in his first large-scale mural project.

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

The hot chocolate here all stems from small, sustainable microproducers in Chiapas and Tabasco.

Gilded heaven for philatelists and architecture freaks, still in full working order despite sitting atop tremulous ground.

A railroad magnate's replica village has become home to a genetic seed bank for rare breeds of livestock.

An unexpected Easter egg lurks in the background of a cherub wall relief at the Breakers mansion.

Two New York rooftops are home to the largest rooftop soil farms in the world.

2,000 barrels of aging beer hidden in a warehouse at the Brooklyn Navy Yard.