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

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

This beautiful Victorian ironwork masterpiece was built to keep London from smelling like poop.

Hidden behind a wall for decades, this masonic lodge was only rediscovered during renovations.

After nearly 60 years, there's still a bear at Paddington Station looking for help.

Abstract dinosaur models in London.

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

A historic London cemetery now serves as a nature park incorporating gravestones & memorial statues.

One of the world's largest collections of pathological specimens.

A Victorian natural history and ethnographic museum with wonderful turn-of-the-century, science-book-esque evolution displays.

The remains of Crystal Palace Great Exhibition of 1851.

Remnants of a Victorian garden feature sitting in public woodland.

The world's first underground farm is in a World War II bomb shelter beneath the streets of London.

A special shop catering to the needs of things that go bump in the night, and also helps kids become writers.

A subterranean ice warehouse that has lain hidden beneath central London for over a century is now open to the public.

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

This shop and gallery is a modern-day cabinet of curiosities, unassumingly positioned along an urban thoroughfare.

360° views of the city plus five floors of optical illusions and hands-on science.

An exercise in radical design and social living that became the epicenter of Soviet spy networks in London.

London's largest outsider art museum.

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

A kaleidoscopic warehouse-maze of handmade neon signs.

This historic abandoned train station looks like a stop for ghost trains.

This grand yet little-visited tomb seems almost carved into the hill it sits on.