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

A Roman spa buried deep beneath the City of London.

The breadfruit-adorned final resting place of the infamous Captain of the HMS Bounty.

An eccentric 18th century naval officer built a ship's quarterdeck on his roof, the inspiration for Mary Poppins's "Admiral Boom."

The wooden telephone box hidden away in London's Piccadilly was the original prototype of the iconic kiosk.

The remains of the great moral philosopher reside in a university in London.

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.

Two plaques commemorate the site of Shakespeare's first theatre.

19th-century scientists would make the pilgrimage here to verify the precision of their measuring sticks.

A glorious pub known for a spiteful printing feud and its famous typeface lost—then found—at the bottom of the Thames.

A mysterious pair of mice eating a piece of cheese is London's smallest public sculpture.

The monster at the center of the Darwin Center Spirit Collection.

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

An small and easily overlooked archaeology museum chock full of Egyptian artifacts.

This legendary stone is of unknown origin, and throughout history has been a literal touchstone for British leaders.

A clock designed to run with perfect accuracy for 10,000 years.

This massive collection of British military artifacts includes the heartbreaking personal letters of the men in the trenches of WWI.

The television series' iconic giant foot was borrowed from this classical painting.

A 2000-year-old Roman amphitheater lies just below Guildhall Yard.

A makeshift shrine to the late rock star is still kept up on the nondescript façade outside 1 Logan Place.

London's smallest police station is barely the size of a phone booth.

The anatomical-pathological collection of a man who changed surgery.

Catacombs turned marketplace.