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.

Yo, Adrian!

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

Mural made of 100,000 pieces of hand blown glass, and until recently, the largest glass mural in the US.

America's most famous museum of medical oddities is home to the remains of Albert Einstein's brain.

World's first "penitentiary," meant to be humane, drove men insane.

Chicago's Navy Pier on Lake Michigan was a training hub for aircraft carrier pilots during WWII.

The last masonry skyscraper ever built reveals a transitional moment in architectural history.

These chunky stone towers out in Lake Michigan are the key to Chicago’s drinking water.

The empty tomb that houses the memories of Roy Bertelli's revenge.

The original vault that held the president's remains still stands, empty, not far from where he was finally buried.

When you visit his grave, be sure to rub the Great Emancipator's nose for good luck.

Frank Lloyd Wright's most iconic home dangles over a Pennsylvania waterfall.

Originally conceived as part of a proposed Arizona State Capitol building in the 1950s, this structure built in 2004 stands as a monument to the architect's legacy.

This architectural triumph is the only Frank Lloyd Wright house in Alabama.

Underneath this water pump, Annie Sullivan helped Keller speak her first words.

Thirteen pastel palaces in downtown Charleston add a gorgeous splash of color to the city.

South Carolina's last remaining slavery auction house is now a museum devoted to its own tragic history.

While many places make the claim, the Library of Congress says this restaurant is the birthplace of the hamburger.

This unassuming home was once “grand central station” for the Underground Railroad.

A hidden network of subterranean passageways lies tangled beneath Indianapolis' bustling City Market.

A park where you can watch the highway zoom past.