The largest of London's subterranean rivers and once a mad, bad center of London life.

These wooden pipes were crucial to providing water to Medieval Edinburgh.

This former train tunnel is filled with lines from a poem crafted by Robert Louis Stevenson.

This small sculpture honors a shuttered bookshop that was the site of a fiery act of protest.

The remnants of a facade from a 19th-century market stall emporium.

A recreation of pop art pioneer Eduardo Luigi Paolozzi's London studio.

A multi-storied painting that depicts the area's rich and diverse maritime history.

17th century streets hidden under Edinburgh were once a breeding ground for the black death.

A sculpture in a secluded garden honors one of Edinburgh's most innovative thinkers and city planners.

This 15th-century structure had a long, tortuous journey to its current location.

A quartet of brightly colored mythical beasts stand sentry at this gateway.

An ornate "graveyard" for some of the country's forlorn building relics.

A public art installation with a nautical themed poem, enhances this pedestrian street.

Inside this cathedral is a shoulder bone belonging to the Patron Saint of Scotland.

An ancient stone with mysterious origins stands in a residential neighborhood.

This abandoned mausoleum from 1815 sits deep within the forest surrounding Callendar House.

Stunningly detailed mosaics in a New York subway station bring life to the Weimaraners of artist William Wegman's work—and to thousands of commutes.

The mystery of this small, brick pond eluded its possibly only investigator until his death.

This sculpture marks the spot where one of the greatest Roman rulers was proclaimed emperor.

Modern megaliths form this work of cosmic, Celtic landscape art.

A carved bench marks the Scottish cave that inspired the classic adventure novel "Treasure Island."

The oldest library in Scotland was built from the remains of a church to hold a churchman's library.

A giant pineapple, a symbol of hospitality, and an amazing vacation rental option.

Chelsea's soldiers were given strict orders when crossing this historic bridge.