A historic area for shopping and dining in Ketchikan's former red-light district.

From overly ambitious (and eventually abandoned) atomic dream to bustling office park.

A tribute to the Nirvana frontman hides beneath the bridge that was the singer's beloved hangout spot.

A tiny red pebble marks what may be the quietest outdoor spot in the United States.

This large Sitka spruce that appears to be floating in mid-air, has defied logic for years.

This tree has witnessed nearly 1,000 years of history.

Shoreline strewn with the remains of ghostly fallen trees.

This 18-foot-tall public art installation is another of sculptor Thomas Dambo's trolls.

The most accurate timepiece in the world.

A celebrity from the late Cretaceous period.

The house where Lincoln drafted the Emancipation Proclamation.

This American Civil War-era fort still stands near the border between Washington, D.C. and Maryland.

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

A Civil War fort in the middle of Washington, D.C. has been swallowed by a forest.

This lifelike sculpture of a policeman serves as a helpful reminder to watch out for crossing pedestrians.

Washington's top-secret Cold War-era doomsday communications tower is located in a small neighborhood park.

The only Civil War battle in Washington D.C. took place near this highest natural point in the city.