The site of Paul Revere's historic two lantern warning.

A centuries-old church stands as a testament to Boston's "father of architecture."

The oldest Italian café in Boston, this spot also serves as a veritable museum of vintage coffee ephemera.

This nearly 200-year-old restaurant's history includes an exiled French prince, JFK, and a very hungry Daniel Webster.

Millions of numbers carved in glass represent the tattoos forced upon victims.

The site where Charles Dickens gave his first public reading of "A Christmas Carol" in the US.

Macabre headstones carved with winged skulls, dancing skeletons, and pithy reminders of impending death.

Statue commemorating the use of ether in anesthesia.

Mrs. Mallard and her brood are a beloved fixture in Boston Public Garden.

The final resting place of the first documented Chinese person in the United States lies in a Boston cemetery.

Berthed at the Charlestown Navy Yard in Boston, "Old Ironsides" is the oldest commissioned warship still afloat.

American revolutionaries and British soldiers alike are buried here in the fourth-ever cemetery in Boston.

A men’s restroom became a sandwich shop.

One of the last remaining World War II Victory Gardens in the U.S. is quietly growing across from Fenway Park.

Its collection includes a broad array of social, geographic, graphic design, and political history.

This coffee shop lies hidden beneath a historic church.

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

This ancient oak plays host to carvings of magical elves, gnomes, witches, and other creatures prominent in local folklore.

You'd never know the houses at 23-24 Leinster Gardens were fakes—until you see the train tracks on the other side.

Home of one of history's most famous cartoonists just as he left it.

This hidden rooftop garden in downtown London offers a quiet respite from a bustling city.

A mysterious carving from 17th-century London seemingly depicts a young boy sitting on a bread basket.

The bridge is a secret gallery of discarded gum that has been transformed into miniature masterpieces.

A wall of chewing gum moonlights as collective art.