An abandoned stretch of highway, deteriorating next to the operational one.

Maryland's first (and last standing) toll house on America's first federal road established the state as the "Gateway to the West."

These abandoned waterworks are crumbling into the Potomac River.

Before Nixon, "watergate" meant canals.

This seemingly out-of-place gas station by the Watergate hotel was once described as the most expensive gas station in the world.

A historic ruin just 20 feet away from a busy highway onramp.

A portal into the bricked up canal that runs through the heart of Washington D.C.

The 5.5-mile ring of steel posts around the Capitol Building is one of the largest (and most uniform) of its kind in the world.

In the basement of the U.S. Capitol Building is a hidden storage room full of ornate floor tiles leftover from the 1850s.

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

A derelict bit of transportation infrastructure hidden in the woods.

A historic estate packed with George Washington's heirlooms, and its own nuclear bunker.

A secretive collection featuring objects that were designed specifically for U.S. intelligence operations.

The span is crooked and made from two older recycled bridges.

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