A modern-day Lascaux cave underneath Paris.

The subterranean "lake" below the Paris opera house inspired the Phantom of the Opera's lair.

A Parisian cemetery where the elite and artistic are interred beneath an eccentric collection of tombs.

Walk upon the mementos of the dead in this Parisian courtyard paved with medieval tombstones.

Folklore and history carved into Brittany's coast.

This pebble beach is so beautiful that taking its rocks is against the law.

This black shoreline is made up of exploded lava particles.

This industrial area was the dumping ground for massive amounts of trash, some of which washes up as tiny bits of sea glass.

Living fossils in this remote Australian bay provide a glimpse of what Earth may have looked like 3.5 billion years ago.

Crushed coral and crystals give the sand its signature coloration.

Centuries-old hoofprints and wagon tracks reveal themselves after a good winter storm.

The eerie remnants of an ancient forest were hidden under the sand for centuries.

A nesting ground for four of the world’s seven marine turtle species, most of which are endangered.

A former hospital is now home to a pizza parlor and maybe a few ghosts.

One of the best places in Florida to spot rare, carnivorous pitcher plants.

This now-deactivated naval base defended the Florida coast for centuries.

The permanent home of a 1960s traveling museum of tiny historical dioramas.

That bass was as bad a fish as any angler ever knew.

A natural history museum with an extensive collection of bird dioramas.

Colloquially known as "the lynching memorial," this is the United States' first memorial to the victims of racial terror at home.

This botanical garden has been nicknamed "Alabama's Little Corner of Greece."

This 12-foot-tall T-rex is the largest K’Nex skeleton sculpture in the world.

Booker T. Washington's home at the Tuskegee Institute was a gem of splendor.

Designed by Maya Lin, the memorial honors 41 individuals who died fighting for equal rights between 1954 and 1968.