Central America's deepest lake is actually a volcanic caldera, surrounded by three volcanoes.

Climb to the top of the world's largest seated bronze Buddha.

An island in the middle of a lake, in the middle of a volcano, in the middle of a bigger lake, in the middle of a bigger island, in an archipelago, in the Pacific Ocean.

This short bridge is the only thing connecting a tiny Irish island to the mainland.

The ruins of this medieval castle in Northern Ireland have inspired artists from C.S. Lewis to Led Zeppelin.

A museum marks and documents the site of the Titanic's launch.

Traversing steep Alpine slopes, this engineering marvel is one of the longest and highest funiculars in the world.

Legacy of the earthquake that nearly wiped Lisbon off the face of the Earth.

See massive fossils that are over 200 million years old in northeastern Arizona.

This iron and wood Civil War city-ship was the first vessel to be sunk by an electrically detonated torpedo.

A grandiose octagonal home crowned by a large dome stands out among the antebellum mansions.

Elvis's own personal tropical hideaway.

The hotel where Martin Luther King Jr. was shot is now a museum dedicated to his work.

The Boston square dedicated to the dark poet who was born nearby.

The most loyal of little dogs, or a Victorian era publicity stunt?

Northern Ireland's Brobdingnagian stepping stones.

Famously misunderstood wonder of the ancient world

The only structure left with direct ties to the Salem witchcraft trials of 1692.

Hear the quietest sound from across the dome.

This ancient Greek place of assembly and marketplace is being revealed layer by layer below the modern Athens cityscape.

Oldest Protestant church in the Middle East, designed to resemble a synagogue.

Built in 1512, the oldest cathedral in the Americas.

A tribute to Ponce de Leon's supposed quest for eternal youth.

Giant six-pack could provide one person a six-pack a day for 3,351 years.