The walls of America's oldest masonry fort famously "swallowed" cannonballs.

In this case, 'zero' marks the spot where the iconic Old Spanish Trail ends.

Abandoned Air Force base that has fallen into disrepair.

Megachurch turned Catholic church comprised of 10,000 glass panes.

The final resting place of the songwriter who penned “Take Me Out To The Ball Game."

A whale of a public art display towers atop Juneau's cruise ship dock.

Known as the “Official Greeter of Juneau,” this dog still welcomes ships and their passengers to Alaska.

A rare chance to get up close and personal with a 13-mile ribbon of ice near downtown Juneau.

This abandoned mine offers a glimpse at what life was like for those who came to Alaska seeking Gold Rush riches.

One of the dwarven trees dates back to 1625 and survived the Hiroshima bombing.

Home to two notable early-20th-century Black educators, Lucy Slowe and Mary Burrill.

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

An atomic bomb-proof strongbox protects the U.S. Constitution from terrorists and thieves.

Legend has it that President Grant’s frequent drinking in the lobby gave rise to the term “lobbyist.”

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

This lovely pocket park is one of the most under appreciated in D.C.

A derelict bit of infrastructure from the canal that once ran through D.C. is landlocked in the heart of the city.

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

The oldest continuously operating fish market in the United States.

D.C.'s first central library was born out of a chance encounter with the philanthropist whose name it bears.

A museum and doll store featuring a surreal and super sanitized version of where babies come from.

A historic gristmill that still produces flour and grits the old-fashioned way.

This lovely burial mound is actually a replica that was installed after archeologists excavated the original.

America's first federal monument.