An emerald-green grotto just a short trip from Austin.

This hidden sculpture garden full of Wild West art is one of San Antonio's best-kept secrets.

A 19th-century architectural wonder designed by the "father of the skyscraper."

The four tall pillars once marked the entrance of the historic Seattle church that fought for women's suffrage and civil rights.

A lesser-known part of the Kinsey Institute is this impressive collection of art, artifacts, and material culture related to human sexuality.

A chapel built by Italian POWs during World War II tells a forgotten tale of the war on the home front.

Down the road from where the Wright brothers lifted off is another flight tribute practically hidden from sight in the woods.

Inside the unassuming cemetery chapel is a magnificent stained glass window and mosaics.

Legend has it the commander of the defenders drew a fateful line in the dirt with his sword just before the final battle.

This colonial tavern played host to George Washington, Thomas Jefferson, and other famous early Americans.

One of the oldest used bookstores in the U.S. has been selling antiquarian treasures since 1825.

Located in Faneuil Hall, the headquarters of the Ancient and Honorable Artillery Company of Massachusetts has stood the test of time.

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

Mrs. Mallard and her brood are a beloved fixture in Boston Public Garden.

The site where Michigan launched its first rocket into space lies abandoned in the dense woods along Lake Superior.

Pensacola's UFO home has withstood many hurricanes—just as the experimental 1960s design intended.

The world’s largest Masonic temple was saved by the White Stripes.

Two small markers remember the Alamo's feline protectors.

Abraham Lincoln's likeness rests at the top of this giant totem pole.

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

This whimsical campus lawn is dotted with large sculpted numbers and hidden mathematical formulas.

The graveyard holding the remains of George Washington's slaves was forgotten for nearly 200 years.

You can walk through the first Boeing Air Force One, which famously carried JFK's casket from Dallas back to D.C.

A slab of sandstone covered with mysterious 1,000-year-old rock carvings from a vanished North American culture.