A spectacular cave and a beguiling lake.

The hallucinogenic center of the ancient world.

London's old-school healing garden.

An alleyway plaque is all that remains of the independent Texas' envoy that forgot to pay their rent for over a century.

The quaint little store that is said to have inspired a famous Dickens novel was only given its name after the book was released.

A 1,215-foot tunnel transports pedestrians beneath the River Thames.

A subterranean ice warehouse that has lain hidden beneath central London for over a century is now open to the public.

A tongue-in-cheek arcade where the games are based on everyday life.

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

The perfectly preserved underground rooms where Churchill plotted the war against Germany.

An easily overlooked stretch of ornate window fronts and gaslight lamps that could be right from the pages of Dickens.

This shop and gallery is a modern-day cabinet of curiosities, unassumingly positioned along an urban thoroughfare.

A kaleidoscopic warehouse-maze of handmade neon signs.

This massive monument was unveiled the day Kosovo declared independence from Serbia.

A 11-foot former president stands on a Kosovo street that also bears his name.

A futuristic, brutalist masterpiece that is also strangely prison-like.

This aromatherapy shop and mini-museum cofounded by the Sigur Rós frontman documents Icelandic history through scents.

Inside this Icelandic greenhouse, geothermal energy keeps tomatoes warm and growing.

Staves, storm-calling, and of course, necropants.

Medicinal spa created with the discharge from a geothermal energy plant.

This controversial Irish show cave is home to a massive formation known as the Great Stalactite.

Once the longest bridge in Ireland, this rusting span sits abandoned and overrun by nature.

A sacred well steeped in Pagan roots on the West Coast of Ireland.

The oldest pub in Ireland may also be the oldest surviving bar in the entire world.