The Byzantine, pre-Columbian, and medieval art at this stately mansion are some of the most under-appreciated collections in D.C.

A three-story tower of books about Abraham Lincoln is one of the more unusual monuments to the president.

Those with a sharp eye can find the hidden image of a German Shepherd on the memorial's Mural Wall.

An overlooked memorial honoring the local Washington residents who died in World War I.

Dogs, cats, horses, monkeys, frogs, and fish are laid to rest at the second-oldest pet cemetery in the U.S.

An astounding collection of medical specimens, including bits of President Lincoln.

A bit of retro transportation flair preserved in the world's largest department store.

This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.

Lady Liberty's first beacon of enlightenment is now displayed in a museum near the statue.

Wall Street has a new heroine, a bronze statue of a small but fierce girl.

This hidden oasis features a stunning view of the Hudson River and the Palisades from a castle-like museum.

Mysterious 500-year-old tapestries depict a unicorn hunt.

Elevated freight railway turned wildly successful urban park.

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

This stunning blue and gold room changed cities twice before becoming part of the Smithsonian.

A traveling postal dog covered 48 states and more than 140,000 miles, and he lives on as taxidermy, patched up with a rabbit's foot and a pig's ear.

The largest ancient burial mound in Ohio.

Known locally as "the giant head," this 14-foot LED sculpture has a photo booth in the neck where you can have a 3D picture taken and displayed.

Perhaps the most scandalous statue of America's first president.

A single handprint, which, according to Ohio State University legend, cannot be scrubbed off.

This small plaza encourages people diagnosed with cancer to never give up hope.

Rare recess caves fill this unbelievably beautiful Ohio park.

A jukebox headstone marks the grave of the Cleveland disc jockey credited with coining the term “rock 'n' roll."

The angel of death appears to weep black tears at this grave marker.