This subterranean spot might be the epitome of Japan's baroque, retro coffee houses.

Years of archaeology, just chillin' by the water cooler.

Try your hand at old-fashioned coffee growing at this museum devoted to one of the world's most coveted beans.

A suburban museum tells the story of a historic transportation network and even provides rides in antique trolley cars.

Exact replica of the ancient monument, but much, much lighter.

An art supply shop holds the secrets of this quiet neighborhood's raucous Barbary Coast past.

One of few lasting examples of the brief octagon craze that developed into folly.

Barely visible foundations remain where Stow Lake’s “observatory” once welcomed visitors.

Amazing meticulous gardens of personal wood carvings, Hydrangea, Canna, and many other flowers.

San Francisco's oldest operating hotel, with a Victorian atmosphere and a "haunted" fourth floor.

Russian history in San Francisco.

Alleyway plaque commemorating the death of a fictional character in The Maltese Falcon, not far from the author's home.

The remains of a 12th-century chapter house in Golden Gate Park.

A promotional sun clock on the site of San Francisco's great raceway.

San Franciscans leave gifts and messages for the magical beings that live behind the tiny, mysterious door installed on a tree in Golden Gate Park.

Guns that have been defending San Francisco since 1904.

The haunting "Hell House Altar" is one of the few remnants of an abandoned college that has been a magnet for local legends.

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

The discovery site of the "Capitalsaurus," the official dinosaur of Washington, D.C.

A dark, dank room in subterranean Manhattan was the site of a ghastly murder.

Rummage through this sunken ship, but leave your scuba gear at home.

A room in New York City that contains 250 cubic yards of dirt worth a million dollars.

Walk over a 150 year old manhole.

Nikola Tesla's former home contains an homage hidden from plain sight.