A plaque marks the underground site of one of London's "lost rivers."

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

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

Some of the earliest leaders of the Moravian congregation are buried here.

This hidden green space is the city's second largest conservatory.

London's only public statue of the much-married monarch adorns the gate to St Bartholomew’s Hospital.

This churchyard arbor is surrounded by hundreds of gravestones placed there by author Thomas Hardy.

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

Dictionary Johnson’s favorite feline.

The last remaining example of the boatmen's perches that once dotted the south bank of the Thames.

The Metropolitan Police refurbished the blue box (perhaps not coincidentally) the same year "Doctor Who" returned to TV screens.

A student driver's nightmare.

Winding paths and ramshackle mausoleums in the oldest "park cemetery" in London.

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

A mysterious pair of mice eating a piece of cheese is London's smallest public sculpture.

The Cambridge pub where Francis Crick announced that he and James Watson had discovered the DNA double-helix.

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

The wooden telephone box hidden away in London's Piccadilly was the original prototype of the iconic kiosk.

A tongue-in-cheek arcade where the games are based on everyday life.

Once thought to be the mysterious work of a witchy prophetess, a well with unusual properties turns objects into "stone".

A 1,215-foot tunnel transports pedestrians beneath the River Thames.

The taxidermied remains of a once-great parrot.

19th century museum with an eclectic mix of curiosities, from Egyptian artifacts to items on archery history to the skull of the world's oldest horse.

A century-old tradition has culminated in a small but singular collection of feline effigies.