The world's largest piece of copyrighted artwork.

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

One of the few remaining monuments dedicated to South Boston's Irish heritage.

This massive tea kettle was once a promotional stunt for the Oriental Teashop.

This giant Boston statue of Mary is standing on a globe to show her power over the universe.

"Mock all and sundry things, but leave the saints alone."

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

Narrowest house in Boston.

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

The site of one of the strangest disasters in history—a wave of deadly molasses traveling at 35 mph.

The Boston square dedicated to the dark poet who was born nearby.

This upscale streetwear store is hidden behind a fake Snapple machine in the back of a deli.

One of the oldest used bookstores in the U.S. has been selling antiquarian treasures since 1825.

An enormous, inside-out glass globe built in 1935.

A simple but powerful tribute to the 20 victims of the 1692 witch trials.

Statue in Salem of the woman who starred as the witch Samantha in the sitcom "Bewitched."

The headquarters in Salem doubles as an occult art gallery.

Hundreds of thousands of concrete bunkers crowd Albania long after the fall of Communism.

What happens when you cross a mayor and a painter?

Once the fallout shelter of a dictator, this sprawling bunker is now a combined history museum and contemporary art gallery.

The Grand Mall in Varna hosts one of the biggest collections of Soviet-era paraphernalia in Bulgaria.

Sofia's legislative center is continuously reinventing itself.

This massive stone and steel monument remembers a century-old battle that cost thousands of lives and nearly destroyed the city.

"Holy Wisdom" overlooks the city that became its namesake.