Tombstones and enigmatic inscriptions hide within a vault beneath a popular London arts venue.

Tucked away in the Tower of London is the weapon once used to execute high-profile prisoners.

The majority of the museum's large collection is held in a storage space open to the public a few times a year.

The last four extravagant street signs of London's historic banking street.

An artistic tribute to the famous singer, just around the corner from where he was born.

The television series' iconic giant foot was borrowed from this classical painting.

A student driver's nightmare.

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

An easily overlooked stretch of ornate window fronts and gaslight lamps that could be right from the pages of Dickens.

A 300-year-old tea shop that brought tea to the English people, not to mention the Queen herself.

One of the few remaining casualties of the London Blitz, this destroyed church has become an enchanting public garden.

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

Architect Le Corbusier built his friend a cubist house to match his impressive collection of cubist art.

An off-the-beaten-path boutique stuffed with an eclectic collection of upcycled goods.

Original cabaret handbills, posters, and feline artwork are a purrfect highlight of the Museum of Montmartre.

The water-powered carriages are long gone, but for over a century this funicular railway has been the fastest route to the highest point in Paris.

Indents in the pavement are all that remain from a grisly death machine in Paris.

A majestic lion statue guards this Parisian botanical garden, and feeds on an unsettling item.

Known as the "Dodo Manège," this carousel features a herd of animals that have disappeared—or may be gone soon.

Medieval museum built over Roman baths that features famous tapestries of a lady and a unicorn.

19th century pendulum and a clock restored by a rogue group of guerilla artists.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

A statue of the legendary Celtic warrior queen who fought the Roman invaders stands in one of the cities she once destroyed.

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