A museum dedicated to the alleged Roswell Incident.

The official atomic museum of the United States explores the explosive and productive history of a much maligned energy source.

This pseudo-steampunk weapons facility is the world's largest wood and glue structure, and packs quite a wallop.

Enigmatic tombs and cave dwellings on the outskirts of a rural village.

The medieval home is still engraved with the symbol of the profession, an eye flanked by two axes.

This almost-forgotten underground dungeon housed several convicts over the years, including Caravaggio.

The fishing boats that moor in this small lagoon enter and leave through a tunnel to the sea.

Overshadowed by other, more famous Maltese catacombs, this ancient burial chamber has one of the best examples of a ritual agape table.

This unique building in the main square stands out among the city's typically Baroque architecture.

The ruins of a megalithic monument sit right in the garden of a luxurious Maltese resort.

This prison on the Maltese island of Gozo is almost 500 years old, and they have the graffiti to prove it.

An abandoned set from the 1980 film "Popeye," claimed and repurposed as a theme park by creative locals.

Seemingly grown on some other world, these New Mexico rock formations look like a disused science fiction set.

One man has carved a number of natural New Mexico caves into psychedelic sandstone temples.

Twice a year, visitors can tour the desolate site that birthed the Atomic Age.

The symbol was surreptitiously built into the river bank by German prisoners of war.

In a largely deserted ghost town, a little brick building recalls its history as a gold rush hub and haven for outlaws.

A famous flea market artist's studio that's full of odds and ends.

Life-sized sculpture of a blue whale made of hand-recycled plastic trash.

These Pre-Columbian petroglyphs contain representations of birds, deer, hunters, and even some early Native flute players.

An immersive environment that is part haunted house, part choose-your-own-adventure, and part jungle gym.

This bleach-white graveyard overlooking the ocean is accessed through a tunnel.

This former sugarcane transport tunnel is now a portal to a lovely beach.

This chapel on a cliff is renowned for its healing powers and was founded on the site of a supposed divine intervention.