The unique waterfall in Iceland's south features a backdrop of geometric black lava columns.

Templar knights fleeing persecution are said to have left this sword in stone as a landmark in 1307.

Seemingly straight out of a fairy tale, a steel chair sits on a tiny island only accessible by stepping stones.

A 17th-century doorway in a small Sabine village is a portal into the mysteries of alchemy.

In the middle of a busy residential neighborhood, a small roofless church being reclaimed by nature.

A castle inspired by medieval architecture is hidden in the woods of Connecticut.

A colossal aqueduct from the second century B.C., deeply hidden in a gorge on the outskirts of Rome.

This burial mound is said to be the final resting place of Russia's first Viking ruler, Oleg of Novogrod.

Abandoned Italianate architecture on the coast of Maine.

At the right time of day, sunlight floods through the roof of this cave and illuminates the small pavilion hidden within.

Of all the houses that grace this neighborhood, only one is a testament to surreal architecture.

The Belgian royal family's private depot now stands abandoned and forgotten alongside the tracks.

Cozy basement bar sports an inventory of over 2,000 beers.

Climb inside an iron crystal magnified 165 billion times its normal size.

Visitors are treated to a stained glass kaleidoscope interior inside this work of art.

The only surviving piece of Copenhagen's 16th-century defensive wall.

A novel collection of medical curiosities housed in an 18th-century surgeon training academy.

Climb to the top of its spiral spire for spectacular views of Copenhagen.

The old observatory in Copenhagen has a spiral corridor used as a racetrack.

This sublime architectural marvel is a rare example of an expressionist church.

Pre-Nazi swastikas adorn the sculpted pachyderms flanking this brewhouse portal.

The de facto symbol of Copenhagen is this bronze fairytale which cannot seem to keep its head for very long.

Copenhagen's celebrated theme park and gardens.

The shell of a medieval fortress offers commanding views of the area it once protected.