This impressive Boston holy house is the American mecca for Christian scientists.

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

An easy-to-miss plaque marks the building that first held this 19th-century telephone innovation.

"the sweltering inhabitants of Charleston and New Orleans, of Madras and Bombay and Calcutta, drink at my well . . . The pure Walden water is mingled with the sacred water of the Ganges."

The author of Uncle Tom's Cabin was neighbors with Mark Twain while living in this Connecticut home.

The former home of Samuel Clemens and family remembers the happiest period of the author's life.

Eco-friendly island mansion.

This opera house along the banks of the Connecticut River has two Tony Awards to its credit but it’s never staged a single opera.

Holding multiple historical boats and an entire 19th century village, this New England attraction is the largest maritime museum in the world.

Built as a gift to the hottest tastemaker of the time, these hidden quarters remain an Art Deco showpiece.

A pedestrian island in the middle of world-famous Times Square emits a strange (and purposeful) humming noise.

Ancient ruins hidden underneath a modern luxury hotel.

Public outcry led to this bridge's unique character which celebrates a giant frog battle and also sewing.

Quirky castle designed by the American actor best known for portraying Sherlock Holmes on stage.

The world's largest indoor go-kart racetrack is hiding in Connecticut.

This small-town pizzeria won the Hollywood lottery.

Want to build a wind turbine? Secede from the nation.

With some 500,000 books across five buildings, this bookstore is a reader's paradise.

Ruins of a historic medical facility sits eerily by the water.

Made of bronze and wearing a blue gown, this lady sat in the same location in the Yantic Cemetery for more than 119 years.

Erotic art covers the walls of the largest ancient pleasure palace.

The last moments of the ill-fated Pompeiians, frozen forever in plaster.

Ancient snack bar of the Roman Empire re-opened.

An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.