Carved by a waterfall in a hard-to-reach rock formation, this heart-shaped rock has inspired romantics for decades.

Where America's first doomsday cult awaited the end of the world.

Pompeii's less famous neighbor is still revealing her secrets.

The oldest surviving bridge in New York City, which reopened to pedestrians in 2015.

Ruined 11th century abbey built by King David I in Edinburgh, Scotland.

An underwater city for the dead.

The remains of a failed attempt at medieval nerdery are hidden deep in the woods of Virginia.

An unusual round church in London with a Templar past.

Stunning wetlands ablaze with pink lotus flowers.

Mother Nature outdoes herself with this stunningly beautiful set of caves carved into marble.

A prohibition-style speakeasy takes up residence in the last Victorian residence in Hollywood.

Become a prohibition rebel.

A stunning, two-tiered waterfall made famous by poets, artists and the legend of a ghost dog.

Banksy gives themself artistic license with this piece of London street art.

A beautiful geyser under environmental threat.

Hellam Township is reputed to feature seven remote gates, which when passed through in the right order, open an entrance to hell.

A massive underwater sinkhole made famous by Jacques Cousteau.

This fantastical waterfall is hidden in a cave located in a cracked cliff.

This strange seaside tower got its name from a wealthy eccentric who would hide coins among its stones.

Paris' linguistic guide to the international language of, yes, love.

The deepest lake in the United States, and once the site of epic destruction that lives on in legends.

With over 100 jam-packed rooms to explore plus elaborate tea services and events, the Mansion on O Street is a hidden treasure.

The first declared National Monument in the United States.

This massive stained-glass masterpiece is thought to be the largest Tiffany dome in existence.