This lonely waterfront memorial to the men of the Titanic was erected by the "Women of America."

A bas relief commemorates the "Nuns of the Battlefield" who cared for soldiers on both sides of the conflict.

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

Look closely and you’ll notice that the color changes a third of the way up the tower.

A line of blue paint marks the route of the inaugural parade.

This nine-story building is the oldest standing skyscraper in D.C.

An Industrial Revolution-era public work that purified water using nothing but sand.

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

The "lovely red Vega" of the legendary record-settling pilot.

Home to items never before seen by the public.

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

A much-maligned monument to teetotalism.

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

One critic described it as "middle Mussolini, early Ramses, and late Neiman-Marcus." Another called it an architectural "natural disaster."

A hidden gem on the lawn of the U.S. Capitol Building designed by landscape architect Frederick Law Olmsted.

Members of Congress have traveled between the buildings on Capitol Hill for a century hidden from tourists, press, and storm clouds.

The privately owned cemetery that holds room for Washington's finest when they step down from life.

Need a hardcopy of the 50-title Code of Federal Regulations? This is the place.

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.

Once the supplier for noteworthy projects like the National Cathedral, this old brickworks now lies abandoned.

Housing the National Women's Party since 1929, this historic house is now a monument to the fight for gender equality.

The United States Capitol's former columns still stand.

A historic arena where the Beatles played their first concert in the U.S.

Art deco landmark on the outskirts of Washington, D.C.