The last remnants of Fort Pitt also hold the distinction of being the oldest structure west of the Allegheny Mountains.

The last street in Pittsburgh that's paved with wood.

There aren't too many operational funiculars around, but Pittsburgh has two!

The United States’s oldest funicular railway glides up and down a steep Pittsburgh street.

A hidden gem, named after a San Franciscan icon, offers spectacular views of the Pacific Ocean.

The longest continuously operating Elk's Lodge in the country.

The neighborhood church casts a breast-shaped shadow that locals have come to call the “two o’clock titty.”

Only hotel where you can legally launder money.

Once the largest windmill outside of Holland, with enormous 114 foot sails.

This grinning pup statue is all that's left of what was once a ubiquitous Bay Area diner chain.

Inside this museum, the history of the Walt Disney Family empire is on full display.

One of the oldest producers of hand-folded fortune cookies still uses its original secret recipe.

San Francisco's oldest surviving monument and meeting place for 1906 survivors.

This concrete tangle of square pipes has stood as a proud thorn in the city's side since the '70s.

San Francisco's urban bison herd has persisted in the face of extinction, development, and disease.

The last remaining relic of San Francisco's glittering 1915 Panama Pacific Exposition.

San Francisco's newly reopened hands-on science museum.

The seawater playground of gilded-era San Francisco burned to the ground in 1966.

Tiki luxury on Nob Hill.

Its buzzing collection honors vibrator history.

Relics of the 1894 Midwinter Exposition continue to delight visitors today.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

One of Philadelphia's largest murals resides hidden under this bridge.

The sounds of the world's largest fully functioning pipe organ dazzle shoppers at a Philadelphia Macy's.