A painfully obvious spy house sits right across the street from the Russian Embassy.

The most accurate timepiece in the world.

The site where Poe “in great distress, and ... in need of immediate assistance” likely died.

Miles of man-made caves and tunnels are currently used for cultivating mushrooms.

The great Italian Renaissance painter was laid to rest here in the Chapel of Saint-Hubert.

The reconstruction of this prominent building fulfilled a long-written command.

This ducal residence was once home to a future Russian empress and a French king in exile.

Mysterious heaps of stones dot these otherworldly woods.

This sculpture by artist Fritz Keonig survived the 9/11 attacks and now stands as a monument to the victims.

Standing atop 2nd-century Roman ruins, this church is one of the oldest and most iconic in Old Cairo.

One of its engravings is believed to be among the first representations of medical and surgical instruments.

This ancient structure is widely thought to be the oldest intact pyramid in the world.

Known as the Sistine Chapel of Egypt, this tomb houses some of the most well-preserved paintings in Egypt.

These Egyptian statues have survived for 3,400 years and were an acoustic wonder of the ancient world.

Ozymandias’ time-keeping temple.

Created as a "model concentration camp" to hide Nazi atrocities from the international community, this former camp-ghetto now holds a museum and memorial honoring the lives lost within.

This Gothic church was wheeled in its entirety to a new location a half a mile away.

Every part of this unusual home is built into the sandstone rock.

Underneath the city that invented pilsners are a series of historic tunnels that have been storing beer for centuries.

The soulless eyes of 82 bronze children stare on forever in remembrance of a horrifying World War II massacre.

These 17th-century mummies are no longer naturally preserved, but remain on display today.

Two monstrous faces loom over a village in Czechia.

This museum housed in a former brothel explores the past and present of sex work in Amsterdam.

This abandoned secret city is a crumbling wonderland of Soviet ruins.