Once the largest gravity dam in the world.

The only surviving building of historic West Boylston, which was flooded to create the Wachusett Reservoir.

This Tudor-style mansion is home to the first roadside confectioner in the United States.

The world's most comprehensive collection of Willard timepieces is a celebration of early American clockmaking.

A grave surprise in the downtown area of New England's second-largest city.

A comic book store got the road by its shop officially renamed after Superman's girlfriend.

A museum designed by and dedicated to P.T. Barnum in the town where he is buried.

From lefty Jewish gathering site to hip cultural site in just 80 years.

A grand Gothic Revival basilica with stained glass depictions of Montreal's religious history has only one soul resting in its crypt.

A glass display case holds the document that ended the Second World War—which one person signed on the wrong line.

Once a strategically imperative naval base, portions of this Bermuda dock complex now serve cruise ships.

The larger of two volcanic peaks rising out of the crystalline waters of the Caribbean.

Come for the springs; stay for the mud bath.

One of the few surviving Panama Canal steam shovels stands outside a tiny Colorado mining museum.

Inspired by a music box, a small town Vietnam vet carved an entire carousel full of animals by hand.

A 250-year-old timepiece-automaton adorned with golden mechanical birds, which still sing to this day.

These enormous, stern-faced statues greet visitors with lanterns, and sometimes costumes.

This irregularly shaped sea fortress has defended not one but three different sovereign states.

A subterranean house of worship carved right out of the bedrock.

An abstract monument to a symphonic composer.

Gargantuan home of Russian science.

The gorgeous entrances into the city's underbelly look more like grand halls than subway stops.

The only visible reminders of an elaborate engineering project that kept the tower from reaching the tipping point.

Medieval torture techniques with a modern conscience.