These abandoned grain silos and tunnels are an urban exploration dream.

Nonprofit art center that promotes outsider, intuitive, and self-taught art.

A gothic church spire sits atop this skyscraper, the tallest church in the world.

An antiquated German apothecary on Chicago's North Side.

A monument to the art of slicing people open.

Four glass boxes hover over 1,000 feet in the air to give visitors an unparalleled view of Chicago.

This massive stained-glass masterpiece is thought to be the largest Tiffany dome in existence.

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

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

This landmark cemetery in Boston was created more than 300 years ago.

19th-century operating theatre in which the use of ether was first demonstrated - plus, a skeleton and a mummy!

The often-overlooked ruins of one of the first buildings designed by famous landscape architect Frederick Olmsted.

Dim sum, served in a grand old theater.

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

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

What may be Boston's finest Art Deco building, located in the city's Financial District.

A plaque marking the famous abolitionist's birthplace often overlooked by visitors to the nearby Charles Sumner House.

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

Site of a famous 19th-century transcendentalist utopian community, now abandoned.

Colorful clay cliffs tower over an unofficial nudist beach on Martha's Vineyard.

One man’s hobby is another man’s world of metal wonders.

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

It was an experiment to prove that glacial boulders and rocks can be used in constructions and dwelling.

This railroad tunnel was once the longest in Massachusetts.