Medieval torture techniques with a modern conscience.

Secret refuge and museum of the Duke of Florence.

This palatial spiral staircase was so unusual the name "snail" was given to the noble family who built it.

This deconsecrated church has seen many uses, from a tobacco storehouse to a cinema.

A new sculpture calls attention to climate change in the centuries-old city it threatens.

In the past, Renaissance sex workers were encouraged to entice customers on this bridge.

According to tradition this is the oldest church in Venice, but its actual age is a mystery.

Two stone columns flank the grand Venice square, but there were supposed to be three.

Go inside to really appreciate this 500-year-old technological masterpiece.

This fountain is dedicated to the workers who perished constructing the Fréjus Rail Tunnel.

A Spanish-style estate that has traded black ties for rock concerts.

Spanish architects used seized Muslim gravestones to rebuild parts of the fortress.

A 16th-century Andalusian palace.

The current seat of the Parliament of Andalusia was once the epicenter of the Great Plague of Seville.

The final resting place of the great navigator, or maybe his brother.

This ornate church designed by a self-taught architect is an eclectic masterpiece in the heart of Central Mexico.

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

CDMX's home for the world's culinary delights.

At a museum of everyday objects, it is the act of collecting that is really on display.

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

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

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

One of the oldest colonial buildings still standing in South America.

These egg-shaped buildings constructed by Jesuits house a quaint museum in the Andes.