When the water level in the Danube in central Budapest is low enough, there is a secret site telling the history of one of the most iconic bridges of the city.

One part local history, 99 parts gruesome haunted house.

A hands-off space for graffiti artists to hone and display their skills.

The bronze uniforms commemorate the vital role of women during World War II.

An unusual ode to the late Irish playwright, complete with a squiggly bust and coffin-shaped bench.

The pretty iron lamp is a reminder of the architecture underneath London's streets.

This black cat was actually designed to ward off bad luck.

England's most famous front door has an accidental doppelganger.

The broken skateboards that became a poignant memorial to a murdered skater.

Legend says these colorful, invasive residents are the descendants of birds released by Jimi Hendrix.

A set of outdoor stairs named in honor of a famous Austrian artist.

A monument dedicated to a lone, brave invader.

The solemn exterior conceals an opulent interior of this 17th century church.

This museum is dedicated to the little known ancient Roman history of Vienna.

On a winding Vienna side street, one museum has turned their windows into a monument to history’s peace-minded heroes.

The beautiful baroque library of the Hapsburg empire.

In the middle of a Vienna square, Roman ruins dating back some 2,000 years are on display.

Baroque celebration of the end of the Great Plague of Vienna.

This impressive working clock made of 16,000 plants changes its flowers twice a year.

Soaring over the Niagara Whirlpool since 1916.

A tunnel that brings more than a century of history to life from the deepest parts of the Niagara Gorge.

A mechanical clock built in 1914, with a rotation of 12 historical figures on its face.

These two 15th-century metal rods allowed people to check if they were swindled or not.

One of Vienna’s oldest (and perhaps most haunted) alleys, allegedly with a bloody past that gave it its name.