The nearly 200-year-old folly has a secret spiral staircase hidden in one of its pillars.

This imaginative sculpture is a memorial to this town's former mining industry.

A well preserved remnant of the English Civil War.

This natural "sea of stones" was once used by the Romans as a quarry.

This park and coal mine heritage site is home to two of the last steam winding engines in the UK.

Constructed 20 years ago, this sculpture is slowly fading to the hands of time.

An iconic and controversial ancient Iberian funerary urn with a hauntingly penetrating gaze.

The surviving remnants of a destroyed medieval church now stand in a public park.

A real-life Professor Snape once taught in this Welsh university building, which students of course nicknamed “Hogwarts.”

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

The sanctuary seems to either float atop the water or sink into the dirt, depending on the water level.

This Scottish bay still reveals evidence of its days as a seaside swimming pool.

This rare aquatic phenomenon is one of the more accessible tidal bores in Morecambe Bay.

This former coal mine, now a fascinating museum, was the site of Belgium's worst mining disaster.

Walk through the history of a Dutch truck manufacturer, from 1928 to today.

Also known as Napoleon's Canal, this waterway was created on the orders of the general, and construction was interrupted by Waterloo.

This bell tower is the only one of its kind in the Netherlands and was a symbol of prestige.

This abandoned viewing platform has become a monument to unnecessary government spending.

The last Oostende trawler to fish off Iceland is now a museum.

This whimsical, unique clock has been entertaining shoppers for well over 20 years.

This former World War II torpedo testing location is now an important nesting site for migratory birds.

This giant weaving shuttle celebrates Lancashire's importance during the Industrial Revolution.

The granddaddy of English geoglyphs dates back to the late Bronze Age.

Andrew Carnegie funded the building of almost 3,000 libraries across the world, this was the first.