Bangkok celebrated its shifting monarchy with a militaristic homage to democracy.

A plaque marks the site directly below the mid-air detonation of the atomic bomb over Hiroshima.

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

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

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

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

These official units of measurement—including chains and perches—lie hidden beneath tourists' feet in a popular London hub.

London's smallest police station is barely the size of a phone booth.

A statue of the original Pearly King is hidden in a church's crypt.

Installed at a chaotic intersection, this gave London traffic cops a place to hang their heavy woolen coats.

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

The world's first and only escalator for lazy bicycles and their daunted riders.

This hidden Art Nouveau courtyard is an opulent feast for the eyes.

2300-year-old Roman road connecting the empire.

An alchemist's "magic door" stands in the middle of a Roman park.

One of Catholicism's four major basilicas has a series of papal portraits that are said to predict the end of the world.

This chimerical bridge/tunnel appears to dead end right into the sea.

Danish observation tower designed to look like a giant beer bottle.

The design of this beautifully crafted building was inspired by Norwegian glaciers.

This hidden green space is the city's second largest conservatory.

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

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

Frequent fliers welcome in this airplane hotel.

It houses the remains of a 17th-century version of the Titanic.