The first American department store, and home to the largest operating musical instrument in the world.

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

Dr Barnes' $25 billion private collection of art and arboretum.

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

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

The world’s first penitentiary, meant to be humane, drove men insane.

Alexander Hamilton’s creation caused quite a bit of controversy.

This charming colonial alleyway is one of the oldest continuously used residential streets in the U.S.

This hidden gem of a garden has one of the only surviving Victorian ferneries in America.

One of the world's largest model railroads is a mind-boggling achievement.

Frank Lloyd Wright built this suburban synagogue late in life, but it stands among his most iconic masterpieces.

This strange, big-tailed beast became a Pennsylvania town's unofficial mascot.

A bronze monument to the infamous radio broadcast in the real New Jersey town where the fictional Martians crash-landed.

The final resting place of many of New Jersey's most famous residents, including U.S. history's most in-vogue antagonist, Aaron Burr.

The mysterious canine hides atop a drain pipe on the back of the building, some say as a sneaky shoutout to Yale.

Nassau Hall has served as army barracks, a museum, and played a key role in the American Revolution.

These 20-foot sculptures will help guide you from the local train station to the local sculpture garden.

A unique sculpture park that specializes in the huge and bizarre.

This Delaware River bridge is emblazoned with a catty slogan from a more prosperous time.

The world's longest known cave system.

America's post-nuclear-attack chambers of Congress.