One of the world's steepest streets seems to have houses sliding down it.

The water-powered carriages are long gone, but for over a century this funicular railway has been the fastest route to the highest point in Paris.

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

An architectural oddity hides in plain sight on this iconic London bridge.

The Great Fire of London and the regulation of one-way streets both started in this alley.

The commemorative stone column conceals a secret laboratory.