Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

This crumbling medieval basilica once attracted pilgrims by the thousands to collect a miraculous dust that formed above the saint's tomb.

The ancient latrines of the Greeks, in all their public glory.

In this historic region, homes and churches are carved into ancient volcanic rock formations.

A charming beach town in Turkey captures all the colors of the rainbow.

This crucial gathering spot along the "hippie trail" still displays old notes between traveling beatniks and backpackers.

Legend says if you stick your thumb in the hole and it gets wet your wish will be granted.

A marvel of Byzantine engineering under the streets of Istanbul.

Brass cobblestones mark the places where individual Holocaust victims were taken from their homes.

More sculpture than building, this architecturally significant temple was built on the spot of Saint Peter's crucifixion.

The final resting place of the poets Shelley and Keats.

2300-year-old Roman road connecting the empire.

Rome's semi-secret peephole vista is also a former Crusader stronghold.

A slightly creepy gallery of plaster cast models in the same museum as Michelangelo's David.

Renaissance hospital featuring a rotating door into which unwanted babies were dropped.

This stone complex marks the urban center of a lost civilization.

On the coast of Sardinia, a once-great mining village is finding new life as a coastal resort town.

This one-of-a-kind archeological site is home to strange prehistoric ruins, the original use of which is still a mystery.

This elaborate hole in the ground was built as a sacred site for an ancient civilization.

A striped 12th-century basilica sits in the countryside of Sardinia.

This Tuscan lake hides a 13th century town that is still visible when the water recedes.

The design of this beautifully crafted building was inspired by Norwegian glaciers.

This Norwegian satellite station provides ground services to more satellites than any other facility in the world.

In the northernmost city in the world, it's illegal to be buried because it’s too cold for bodies to decompose.