An underwater restaurant, surrounded by a coral reef.

Earth's tallest volcano is sacred to Native Hawaiians, and home to a dozen world-class observatories.

Twenty-seven massive radio antennas on the high plains of New Mexico search for life on other planets.

A historic observatory precariously perched at the "Top of Europe."

The world's largest neutrino telescope searches for secrets of the universe at the South Pole.

Site of the world's largest nuclear explosion.

The convergence of two currents makes this a surprisingly pleasant getaway in the Arctic Circle.

The world's northernmost aquarium looks like it has fallen over.

Former headquarters of the KGB.

Moscow's most popular cemetery includes the graves of numerous cosmonauts.

Museum celebrating the achievements of the Soviet space program.

The coldest city in the world.

The villagers of the coldest inhabited place on Earth adjust to unique challenges presented by day-to-day living.

A subterranean Holocaust refuge within one of the world's longest cave systems.

The largest catacomb system in the world.

Across the Pacific in a raft, a museum dedicated to Thor Heyerdahl's now legendary expedition.

Home to three historic ships from the age of Vikings.

Longest road tunnel in the world features an air treatment plant and the illusion of daylight.

The first evidence of some of the Earth's earliest life was found in this fossilized undersea grotto.

Cold storage for agricultural biodiversity.

The ghost town left by the worst nuclear disaster of all time is being taken over by nature and urban explorers.

This uninhabited volcanic island is the most remote in the world.