Mysterious 500-year-old tapestries depict a unicorn hunt.

This whimsical group of statues is a favorite of children who love to climb all over Lewis Carroll's beloved characters.

Collapsing castle on the Hudson river was once the storage site of military surplus business.

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.

Elevated freight railway turned wildly successful urban park.

A statue honoring 44 continuous years of greeting passing ships.

This quirky curiosity shop takes its cues from the world's bazaars.

This volcanic cave lake is essentially hard proof that Iceland is the most magical place on Earth.

Instead of solid circles, the stoplights in this northern Icelandic town have glowing red hearts.

The picturesque birthplace of Icelandic democracy is drenched in the blood of its brutal past.

This stunning concert hall has become a symbol of Iceland's national recovery.

A sulfuric martian landscape that looks far better than it smells.

These ominous lava formations were said to be an entrance to the netherworld so of course they inspired a famous metal band.

If a glacial river suddenly diving into a sheer chasm via a dramatic, multi-stage waterfall isn't peak Iceland, it's certainly close.

This valley of hot springs and boiling mud pots is home to the record-holding "Geysir," which originated the English word.

This elegant arc of a waterfall marks a religious turning point.

This eye-popping Icelandic crater lake is surrounded by red volcanic rock.

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

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

Behind one of the world's most impenetrable vaults is a massive collection of retail silver.

The watery entrance for condemned prisoners heading to the Tower of London is still visible along the Thames.

You'd never know the houses at 23-24 Leinster Gardens were fakes—until you see the train tracks on the other side.

Six ravens are kept captive (but well-fed) at the Tower of London to prevent the fall of the Crown.

The popularity of Sherlock Holmes led to the creation of his fictional address, turning the orderly London street numbers askew.