A working model of the entire San Francisco Bay and much of the Sacramento River Delta, complete with regular tides that change every 14 minutes.

This infamous prison has a store where you can buy goods crafted by incarcerated people.

Frank Lloyd Wright died a year before construction on his largest public project even began.

The unedited photograph called "Bliss" has graced the screens of over a billion computers.

Portugal’s highest lighthouse has one of the most impressive focal planes in the world.

This glass skywalk offers vertiginous views down the volcanic cliffs to the beach below.

Radioactivity still cause for concern at this urban explorer's paradise.

Overlooking the Colorado Convention Center is this giant sculpture made from thousands of triangles.

The spot in the Mile-High City that's exactly 5,280 feet above sea level (at least for now).

A Rocky Mountain city provides a happy ending for a pinto pony and his Brobdingnagian red chair.

This museum offers an actual time machine back through Colorado's past.

A downtown park built on top of unclaimed graves.

Travel through the wholesome amusements of yesteryear at this charming miniature village.

The largest self-built castle in the U.S., six decades in the making.

The highest bridge in America was built for an almost unnervingly small amount of money.

A renovated hotel is bringing new life to a nearly-abandoned mining town in Colorado.

Inside this casino, visitors are treated to slot machines and a rare German Christmas pyramid.

This Colorado hiking trail provides a small gold mine of abandoned gold mines.

Thanks to a quirk of elevation this gift shop produces magic doughnuts that are found nowhere else on Earth.

Hidden beyond a kitschy giant beetle is this remarkably sprawling collection of preserved insects.

Air Force Academy Chapel made of 100 identical tetrahedrons works to inspire those of all religions.

This super steep hike ascends 2,000 feet in less than a mile.

Hidden beneath a bridge, this waterfall is known for the large amounts of graffiti painted on its base.

This enigmatic building features numerous architectural styles.