Once the largest public hospital for the mentally ill was also surrounded by controversy.

This valley of hot springs and boiling mud pots is home to the record-holding "Geysir," which originated the English word.

The former home of the Nobel Prize-winning American writer is now home to dozens of six-toed cats.

This legendary "evil" doll has been haunting the citizens of Key West for over 100 years.

An imposing pair of sphinxes stand guard outside this Egyptian Revival tomb.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

This church houses the tomb—but not the remains—of St. Nicholas, the likely progenitor to Santa Claus.

An underground network of massive stone arches and their skylit vaults support ruins of portico structures above.

This arch granting triumphal entrance into Antalya was designed to honor the emperor's visit.

The deepest underground city in Turkey was designed to protect 20,000 people behind massive stone doors.

A deadly ancient portal to the underworld.

A Lycian city of the dead carved into the hillside of Southern Turkey, complete with startlingly human touches.

St. John the Baptist's forearm is housed in this remote 11th-century monastery.

After witnessing the rise and fall of three empires, this ancient city was finally destroyed by a series of earthquakes.

These abundant, over-the-top monuments are so widely scattered that they define the entire compact capital cityscape, often leading to jokes about whether there are more statues than residents.

A mosaic monument that commemorates the historical struggles of the people of North Macedonia.

This elegant monument to those who fought against fascism is inspired by the shape of the poppy flower.

In the hometown of the Catholic saint and Nobel Peace Prize winner, a memorial dedicated to her legacy.

Depending on the region's rainfall, this church may be partially submerged.

The cross-shaped memorial is filled with kitschy tributes to the late pop star.

It's unclear what caused the fire that led to this opulent hotel's demise.

An abandoned resort in North Macedonia is a relic from the Communist Party of Yugoslavia.

This 3,800-year-old site contains markers used to study the movement of the sun and moon and create a lunar calendar.

Space-age monument to an early 20th-century uprising.