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

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

A Victorian natural history and ethnographic museum with wonderful turn-of-the-century, science-book-esque evolution displays.

An alleyway plaque is all that remains of the independent Texas' envoy that forgot to pay their rent for over a century.

Hear the quietest sound from across the dome.

Rebuilt remains of a temple to Roman god Mithras.

Eighty million natural history specimens call this gargantuan museum home.

This London pub hides a peculiar secret: a recreation of the rooms shared at 221b Baker Street by Sherlock Holmes and Dr. Watson.

Hidden beneath the streets of London is a secret subway that only carried mail.

The perfectly preserved underground rooms where Churchill plotted the war against Germany.

The popularity of Sherlock Holmes led to the creation of his fictional address, turning the orderly London street numbers askew.

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