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.

Washington's iconic carousel has a nice piece of Civil Rights history.

The most accurate timepiece in the world.

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

A haunting tribute to pioneering photographer Clover Adams.

The oldest building in the District of Columbia was preserved because of a mistaken connection to George Washington.

This imposing Masonic temple a mile from the White House was the first public library in Washington, D.C.

Home to a vast and influential collection of Shakespeareana.

Largest Roman Catholic church in North America.

The actual model from the original "Star Trek" series is now on display at the National Air and Space Museum.

The beloved statue at the National Academy of Sciences is oh so inviting to sit on.

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

The winding route passes through an enclosed alleyway, two tunnels, and leads to the White House basement.

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

Fittingly, America's museum of architecture is itself a magnificently designed old building.

A monument in Washington D.C. marks the spot from which all other roads were supposed to stem.

A cavernous three-story, 43,800-square-foot basement that was forgotten about for 60 years.

There's a 12-foot-tall replica of the Washington Monument hidden under a manhole nearby.

Enormous piles of historically significant stones, dumped by Congress in a forest, and abandoned for 60 years.

This grand gothic brewery has been pumping out suds for over a hundred years.

A gorgeous mural outside a beloved D.C. restaurant pays homage to famous Black Americans.

The world's oldest soul food restaurant is also one of its best.

The oldest continuously operating fish market in the United States.

When it opened during the final years of the embargo, all the drinks and cigars were free.