The perfectly preserved underground rooms where Churchill plotted the war against Germany.

Hidden beneath the streets of London is a secret subway that only carried mail.

This South London cemetery holds the remains of more than 15,000 people.

Kings Cross Station pays tribute to its role in Britain's best-selling book series.

London's creepiest cemetery was once the site of dueling magicians and mobs of stake-carrying vampire hunters.

The iconic boulevard is the perfect place to catch sight of a bicycling skeleton, a levitating Satan, or a chef with his head stuck in a pizza.

Turntable anonymously received orphans, alms, and groceries.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

Construction of Barcelona’s iconic (but controversial) church was finally completed in 2026—a century after the death of its architect.

An imperial fortress city that incorporated cultural elements from the entire Mughal empire, only to be abandoned the year it was finished.

A blooming house of worship for the masses.

The world's second-largest sundial, made entirely out of stone.

More than half of this Indian palace is drowned but it looks all the more spectacular for it.

Built in 1870 at the bridge that connected Buda and Pest, this spectacular incline railway was almost lost forever during World War II.

Budapest's Communist-era statues, banished to the suburbs.

Bullet holes in the church wall are a reminder of the violence that followed the assassination of a high-ranking Nazi officer.

Looming communist pillar with a Czech twist.

Buried five stories underground, this Soviet bunker is packed with gas masks and Cold War paraphernalia.

Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

Macabre astrological automaton clock dating to the late 1400s.

The biggest and deepest Cold War bunker open to the public can be found in southeast England.

Designed by Maya Lin, the memorial honors 41 individuals who died fighting for equal rights between 1954 and 1968.

The remains of an idyllic small town built for the film 'Big Fish' still stand around a rundown main street.

An abandoned shopping gallery built during Fascist Italy tucked in the center of Palermo.