The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."

This fast-food outlet is the only space and UFO-themed McDonalds in the world.

A museum dedicated to the alleged Roswell Incident.

A trio of colossal statues spread across a Dallas neighborhood chart the emergence of a giant robot born of a locomotive and spilled gin.

Niagara Falls holds a special place in Nikola Tesla's history, so they put a statue on it.

One of the Seven Wonders of the Modern World holds the world's tallest metal staircase.

This 1967 experiment in modular architecture was designed to be a new model for urban living.

An interesting decoration on this historic site, this weathervane comes with as many legends as it does questions.

The former site of an all-but-forgotten colonial landmark is now remembered by an often overlooked bas relief.

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

This popular Boston haunt is reminiscent of a time gone by, when slow cafes and sweet-smelling smoke wafting from patios was the norm.

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

A former waterfront market is now in the center of town due to some interesting Boston engineering.

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

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

This old-fashioned carhop restaurant gave the world the waffle cone.

This life-size bronze statue remembers the tallest recorded human in his Illinois hometown.

A hand-built folk art installation covered with messages of God's love.

This abandoned Navy base was transformed into an off-grid alternative living community for thousands of people.

The secret city built by the Manhattan Project.

The first full-scale tunnel built in America is short but scenic.