Nikola Tesla's former home contains an homage hidden from plain sight.

One of the last few places in Manhattan that employed a pneumatic systemic keeps it on display.

The original toys that inspired the beloved children's stories are on display at the New York Public Library.

Hidden in Central Park's Ramble is a troublesome cave buried just beneath the surface.

Try not to get slimed in Tribeca.

A five-story homage to tea times past.

"Purveyors of traditional sweets and vintage treats."

The pockmarks across the building's facade are remnants of the Blitz.

The bridge is a secret gallery of discarded gum that has been transformed into miniature masterpieces.

This marine reptile was discovered by one of the 19th century's greatest fossil hunters.

A relic of Victorian grandeur hides beneath a busy South London road.

Revel in the Victorian splendor of the world's oldest eating establishment inside a museum.

More than a million titles fill the labyrinthine shelves of this prestigious private library.

This long-hidden space above Westminster Abbey now displays the battle gear of the legendary King Henry V.

The taxidermied remains of a once-great parrot.

Taxidermied animals galore, by appointment only.

Shiny Brutalist box commemorates a pioneer of electricity and houses a railway transformer.

These official units of measurement—including chains and perches—lie hidden beneath tourists' feet in a popular London hub.

The fierce beast perches atop a pedestal marking where the historic City of London gates once stood.

A Roman spa buried deep beneath the City of London.

This elaborate Byzantine-style building was designed for a not-so-pretty purpose.

Ship-sized kinetic sculptural fantasy.

The lab where the scientist made his groundbreaking discoveries is preserved on the basement floor of the Faraday Museum.

A little slice of Japan and its aesthetics in London's Holland Park.