Part modern art project, part traditional chapel, this see-through church is only substantial from the right angle.

This unique architectural wonder is also tied to one of the 20th-century's most renowned writers.

Ring the bell to enter a bar that looks equal parts museum and old curiosity shop.

Elaborately carved to showcase the glorious wealth that the age of exploration brought to the Portuguese empire.

This Industrial Age architectural and engineering gem helps visitors and residents alike traverse Lisbon, “The City of Seven Hills.”

An ancient and majestic fortress that played an integral role in Portugal's road to independence.

The world's oldest bookshop still in operation.

This unreal Portuguese palace looks as though it's made from a pile of different castles.

Elaborate tile work in this railway station tells the story of Portugal.

After a night ravaged by bedbugs, it's said King John ordered the creation of this weathervane.

An ancient instrument used to measure the waters of the Nile so Egyptian farmers would know whether to expect famine or flood.

Charnel house at the foot of Mount Sinai.

An alien landscape of chalk-rock in the Egyptian desert.

This half-forgotten fortress was constructed by the Ottoman conqueror of Constantinople.

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

The medieval center of the Islamic world was also once the seat of Saladin's sultanate.

One of the most well-preserved temples of ancient Egypt.

Ancient Egyptian relief, claimed to depict an electrical light.

This unassuming tree stump reportedly traces its roots to the famous pharaoh queen's reign.

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

The site of the climactic scene from the classic horror film is now a historic landmark.

This memorial museum chronicles the apocalyptic destruction of the First World War.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

The most visited, and possibly most controversial, museum in Germany.