A tribute to an explorer and naturalist often overlooked by history.

A mysterious shape catches the eye in this 16th-century painting.

This Puget Sound military post has a long, turbulent history as a gateway to the Pacific.

Sculptor Antony Gormley used chaos theory and fractal growth to design his tallest creation.

A giant scrawl on the skyline of south London.

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

Legend says these colorful, invasive residents are the descendants of birds released by Jimi Hendrix.

A seaside town with no sea in sight.

A labyrinthine network of chambers with a storied past hides below Edinburgh's South Bridge.

The 2,000-year-old beam is tucked within the pedestrian entrance to the old London Bridge.

A sculpture outside London's oldest cathedral honors the Mohegan chief who died while petitioning the king.

A three-piece musical sculpture installed between the subway tracks at Kendall Station near MIT.

Never actually a tree at all, this spot was the site of London's public hangings for nearly 600 years.

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

The Art Deco artwork depicts gilded carriers of deadly illnesses.

London's old-school healing garden.

Hackney's newest private museum and natural curiosity shop.

The body of at least one victim of a construction accident was left behind in the collapsed pylon, buried under tons of concrete.

An 80-year-old plane tree is devouring an iron bench at Ireland's oldest law school.

This neon landmark has been posing this deadpan question to follicly-challenged Dubliners for over 50 years.

A museum that cashes in on its infamous little people while teaching you a thing or two about the Irish fey.

Dublin's "Dead Zoo" serves as a window to Victorian museum design.

The comedy and tragedy of Oscar Wilde is preserved in a Dublin park, captured in a sculpture of colorful stone.

Dublin's most modern, visually spectacular bridge is modeled after Ireland's national emblem.