This old-world mansion with lush gardens is a gem in the heart of Silicon Valley.

A 19th-century cabin built into a hollowed-out Sequoia tree.

This Native American settlement dates back to the Pueblo II period.

The oldest Italian café in Boston, this spot also serves as a veritable museum of vintage coffee ephemera.

Shelves covered in dozens of coffee bean varieties fill this North End institution.

The word "Watergate" will forever be associated with the infamous scandal in 1972, but this fountain is famous in its own right.

A bronze tribute to a legendary Californian, the self-proclaimed "Emperor of the United States."

A striking memorial to the 21 lives lost in an explosion at the Washington Arsenal

Once a thriving business district, this former shopping area is now an urban ghost town in the heart of the city.

Once part of a dam servicing an early 19th century grist mill, the tucked-way falls are a tricky-to-find urban oasis.

This lovely tree was a thank you gift from the man known as "Public Enemy No.1."

A walk through the historic city center, under the streets of Seattle.

A 1,000 pound brass bell commemorates a time when this small maritime neighborhood was actually its own separate city.

This sculpture forces visitors to confront their relationship with space.

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

It took years to decode its mysterious messages.

800 apricot trees honor Silicon Valley's agricultural history.

Art Deco stylings conceal the true nature of this bridge.

The oldest family-run restaurant in the United States is a living museum of New Orleans dining history.

This Gothic castle was inspired by Erik the Red's Viking residence at Brattahlid in Greenland.

Spiral labyrinth hidden in the hills above Oakland, CA.

This hidden labyrinth offers walkers some brief peace of mind.

Staircase winds down the side of Telegraph Hill through gardens, wild parrots flying overhead.

These old stone ruins in the Oregon wilderness were once bathrooms and are steeped in legends of murder.