Long hidden under grime, the politically radical murals of a little known Yugoslavian master are finally getting their due.

This church in Pittsburgh is home to the largest collection of religious relics in North America.

A restored Pittsburgh house of God has been converted to a marvelous house of suds.

The largest clock face in the United States is twice the size of Big Ben and infinitely more ad-sponsored.

Color-coded signs direct drivers on a network of routes designed to avoid Pittsburgh traffic.

This plaque marks a place where one of Hollywood’s most famous dancers got his start.

Sections of the iconic limestone columns have been left uncleaned as a reminder of the city's polluted past.

A portion of the old Pirates stadium over which a defining home run once flew still stands even after the rest of the stadium was torn down.

A model of a dinosaur that was named for Andrew Carnegie stands outside the museum that also bears his name.

The largest university building in the West is a gothic masterpiece containing dozens of theme rooms based on different countries.

The oldest standing Byzantine church in Athens is tucked within a monastery in the middle of an upscale shopping district.

Victorian "Fancy Craft" Hair Wreaths and Relics.

A dramatic, 360-degree recreation of Pickett's Charge in the Civil War.

This historic address is home to the beloved ball and is an almost totally empty building among the most expensive real estate in the world.

Long-abandoned trolley tunnels just a mile away from the White House are turning into an art space.

Hollywood's most famous landmark, the "temporary" sign that has stood for decades longer than intended.

One of the largest artillery pieces in the world sits in a Washington D.C. parking lot.

Two gems of Beaux Arts architecture that have been sitting vacant for years.

Hear, smell, see, taste, and touch history at this immersive Civil War hospital.

This stately mansion, built in 1787 by America's first Secretary of the Navy, is rumored to be one of the most haunted buildings in Washington, DC.

A small token of gratitude from freezing cold journalists who were given a warm haven while covering JFK's inauguration.

This war hero's old shop remembers the fine line between medicine and quackery during the Revolutionary War.

The Grand Ole Opry's big voice came from a small home in rural Virginia where she was eventually buried.

The early data processor factory founded in Washington for the 1890 U.S. Census went on to become IBM.