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

Twisted girders are all that remain of an Icelandic bridge that was wiped out by a combination of volcanic heat and glacial floods.

Giant WWII fortresses that fired 8,000 rounds a minute, now home to thousands of pigeons.

This East End pub gained notoriety as the site where gangster Ronnie Kray publicly shot a rival.

This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the Harry Potter films.

This pump on the bad side of Victorian London betrayed a horrifying revelation about the water supply.

A memorial for public executions that dates back to the 14th century.

Where condemned pirates met their grisly end at the gallows on the River Thames.

A 1,215-foot tunnel transports pedestrians beneath the River Thames.

This virtually windowless mass of smooth concrete is the only Catholic church in the city.