The 5.5-mile ring of steel posts around the Capitol Building is one of the largest (and most uniform) of its kind in the world.

Once home to seven different roller coasters, Glen Echo has undergone many transformations since its founding in 1891.

The romance of early commercial flight still fills this Art Deco destination.

A celebrity from the late Cretaceous period.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

This Parisian café sticks almost exclusively to an ethos of reuse.

Medieval museum built over Roman baths that features famous tapestries of a lady and a unicorn.

A museum of carnival attractions where you are invited to ride the rides.

The celebrated eyesore created by starry-eyed sweethearts.

An all-American grocery store in Paris sells U.S. "cuisine" like Pop-Tarts and Heinz ketchup to homesick ex-pats.

Dedicated to the art of hunting, with juxtapositions of contemporary art.

Down a cobblestone alleyway is a museum dedicated to Romanticism, with a secret garden.

Stroll through retro Paris while shopping for old postcards and discarded doll heads.

A charming flea market shop dedicated to retrofuturistic apparati.

The Sun King's military models, saved from the Louvre.

A museum of magic with a Sadist past.

135 bronze medallions mark a French meridian line which once rivaled the hotshot Greenwich timeline.

The oldest continuously operating fish market in the United States.

The most accurate timepiece in the world.

This daunting 1st century fortress was purportedly the site of one of the most dramatic revolts of the Jewish-Roman wars.

The oldest playground in America.

The actual model from the original "Star Trek" series is now on display at the National Air and Space Museum.

Mrs. Mallard and her brood are a beloved fixture in Boston Public Garden.

J.R.R Tolkien, C.S. Lewis, and other "Inklings" met at the Oxford pub to discuss the now legendary fantasy stories they were writing.