Graffiti from the 16th and 17th centuries cover the walls of this part of the Tower of London.

An incarceration museum on the spot of possibly the oldest prison in England.

This one has sailed five times as far as Sir Francis Drake's famous ship.

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

Originally meant to hold a statue of King William IV, this support sat empty for years. Today, it hosts a rotating cast of public artwork.

The only university zoological museum in London houses extinct animals, bizarre natural history specimens, and a Micrarium of microscopic creatures.

The Art Deco artwork depicts gilded carriers of deadly illnesses.

Drink your espresso at a Victorian-era urinal in this underground-restroom-turned-coffee-bar.

A hidden treasure in London with a rich medieval history, and the resting place of many luminaries.

You can climb to the top of the column built to honor the "father of British inland navigation."

This magical museum celebrates the life and work of a seminal children's book writer (and occasional spy).

Now overgrown, these anti-tank barriers from World War II are sometimes called "dragon's teeth."

This 18th-century folly is one of Europe's rare "garden mosques."

A scale rocket of an Ariane 5 rocket serves as a monument to a pioneer of space science.

Money made from smuggling sugar helped create this wondrous rock maze in honor of the Prussian Queen Louise.

Skeletons dressed in extravagant 18th century royal costumes cavort in the aisles of this German basilica.

Two monstrous faces loom over a village in Czechia.

Folklore says this medieval fortress was plopped atop a portal to hell to trap the demons below.

The walls and ceiling of this Polish church are decorated with thousands of skulls, with another 21,000 skeletons just below.

Naturally formed rock city in Poland.

A mysterious structure left behind on the Polish mountainside, sometimes called "Hitler's Stonehenge".

One of the largest amphitheaters in Europe is a former Nazi gathering place that still stands today.

Gliwice Radio Tower, likely the tallest wooden structure in the world.

People in Poland have rallied to save this unnatural desert from being reclaimed by the forest.