Rippling sand dunes frozen in the Arizona rock.

Buried for centuries, this hidden cellar is all that remains of London's medieval Whitefriars Monastery.

Where condemned pirates met their grisly end at the gallows on the River Thames.

Tucked away in the Tower of London is the weapon once used to execute high-profile prisoners.

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

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

The London statue that imitates passersby.

William Blake claimed to have painted this gothic masterpiece after encountering this nightmarish being in a vision.

A statue of the legendary Celtic warrior queen who fought the Roman invaders stands in one of the cities she once destroyed.

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.

The watery entrance for condemned prisoners heading to the Tower of London is still visible along the Thames.

Richard III supposedly disposed of his nephews' bodies here in an effort to seal his claim to the throne.

The remains of an ancient Roman teenager are memorialized at the base of a modern London landmark.

A plaque hangs near the execution place of the Scottish Independence leader famously depicted in "Braveheart."

The London pub overlooks where the Mayflower was moored before setting sail for the New World.

Six ravens are kept captive (but well-fed) at the Tower of London to prevent the fall of the Crown.

Mary Kelly was last seen here before she was murdered by Jack the Ripper.

Scattered throughout London are ancient remnants of the city's former bounding wall.

A charming 17th-century alley is lined with secondhand bookstores and antiquarian shops.

The site of London's first coffee house has been serving refreshments of one kind or another for 360 years.

A historic house left in "dramatic still life."

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

Rebuilt remains of a temple to Roman god Mithras.