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

Bizarre Cavern.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

The longest escalator in the Western Hemisphere takes over three minutes to ride down.

A gas station has taken the place of the home of the 19th American President.

This remarkably well-preserved Egyptian plinth is pretty well traveled for a giant piece of stone.

A fountain standing as a testament to a doomed alliance.

Ancient serpentine sacrifice holder that has stood the test of time.

A marvel of Byzantine engineering under the streets of Istanbul.

Rediscovered after a century, the father of the American Navy was reinterred in something dredged up from Davy Jones' Locker.

A priceless collection of the Nation's cryptologic history.

The final resting place of the tragic king and queen of the Jazz Age is tucked away in a small Maryland graveyard.

The semi-reclaimed ruins of this canal were once part of an ambitious plan to reroute the mighty potomac.

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

A girls' boarding school inspired by the Chicago World's Fair, once abandoned, now restored to strange and scenic glory.

Giant acorn-shaped 19th century gazebo from which suburban Washingtonians gazed upon the original "silver" spring.

A haunting tribute to pioneering photographer Clover Adams.

Largest Roman Catholic church in North America.

The United States Capitol's former columns still stand.

The privately owned cemetery that holds room for Washington's finest when they step down from life.

A super-sized promotional trick that is now a D.C. landmark.

The "lovely red Vega" of the legendary record-settling pilot.

Light bulbs, scrap wood, and tinfoil comprise this homemade throne of the gods.

Home to items never before seen by the public.