Graham Ibbesons's moving tribute to the victims of England's worst mining disaster.

The little-known second castle that William the Conqueror built in York.

A labyrinthine underworld of tunnels and caverns hides beneath the city.

Believed to be the longest railway bench in the world.

The walls and streets of the ancient city are peppered with penises.

These ruins are a monument to the region's industrial heritage, and the site of England's worst mining tragedy.

Extremely famous in his native country, this Cracovian painter is all but unknown beyond Polish borders.

The former Nazi concentration camp stands as a museum to remember this dark chapter in European history.

Beneath Kraków Old Town's main square lies a hologram-filled medieval market vampire graveyard wonderland.

This grubby wall is said to be one of the Earth's esoteric energy centers.

This Polish cave has housed a dragon, a brothel, and an enduring legend.

A memorial to the beloved brown bear that served in the Polish army during World War II.

Real bones which are said to have belonged to a Polish dragon.

St. Mary's features one of the most spectacularly decorated cathedral interiors in all of Europe.

Amidst towering office buildings, a local pub lives inside Sheffield’s oldest surviving domestic building.

A tribute to the women who quietly kept the local steelworks alive during both world wars.

This magnificent mural was created with over 30,000 colored bricks.

A wunderkammer of gold and silver reliquaries and ancient saintly bones.

The complex has been abandoned since the Croatian War of Independence, barring a stint as a set for 'Game of Thrones.'

An ancient knight and a symbol of the city's freedom.

Gargoyle head that brings good luck.

The bizarre headgear looks like it was made for a fool, not a king.

This tribute to a beloved cricket umpire is a magnet for risqué pranksters.

These medieval monastery ruins are surprisingly overlooked by most tourists.