These Great Lakes sea caves accessible by boat in the summer turn into temples of ice reachable by foot in the winter.

This cave holds a surprisingly colorful variety of geological oddities.

Recognized the world over as the home of the McCallisters in the 1990 movie "Home Alone."

Take a break from all the boring business of death at this funeral home mini-golf course.

This sprawling mini-golf empire is an impressive testament to a disappearing attraction.

The world’s largest collection of angel figurines includes 600 black angels donated by Oprah Winfrey.

With 8,000 pipes this giant instrument is the most versatile theatre pipe organ ever built.

This softly rounded mansion was built without corners not to avoid evil spirits, but to make them more comfortable.

A six-story-tall golden pyramid, surrounded by a moat.

The birthplace of a titan of American cinema.

A house and yard adorned with bizarre concrete sculptures in a Milwaukee suburb.

The spaceship-like theater, which is still in use, was one of the most popular exhibits at the 1964 New York World's Fair.

Literally a million fascinating cartographic artifacts are held in this sprawling university collection.

This holy goods emporium is where priests go for a little retail therapy to outfit their churches.

A tour de force of a fountain, memorializing a man who loved fountains more than anything else.

Contrary to popular belief, this secluded statue doesn't represent Pennsylvania's founder.

A daily replay of the experiment that proved the rotation of the Earth.

Erected in 1697 this Philadelphia bridge is the oldest surviving roadway bridge and perhaps the oldest stone bridge in the United States.

One of the oldest of its kind.

The sounds of the world's largest fully functioning pipe organ dazzle shoppers at a Philadelphia Macy's.

Current docking place of the SS United States, the fastest transatlantic ocean liner.

This elaborate towering structure was once famed for its revolutionary height.

Instruments, apparatus, and rare books all relating to chemistry and its related sciences.

The body of St. John Neumann and his collection of hundreds of relics, on display in a Philly church.