Giant busts of 42 U.S. presidents are sitting in a field in Virginia.

In one of the smallest countries in the world stands an original Salvador Dalí sculpture.

Stunning Roman aqueduct used for 1900 years and still standing.

An architect transformed this abandoned cement factory into his castle-like workshop.

The unexpectedly beloved remnants of a controversial thermal power plant.

An early 20th-century bullring converted into a modern shopping center.

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

Barcelona's historic 19th-century sewers, whose foundations were laid in medieval times, are open to the public for exploring.

A gorgeous, Gaudí-esque stairway constructed in the city of Istanbul by a prominent Jewish family.

The National Park Service’s best-kept secret with views that rival any in D.C.

A tribute to the pop culture icon overlooks this Washington D.C. intersection.

A line of blue paint marks the route of the inaugural parade.

This seemingly out-of-place gas station by the Watergate hotel was once described as the most expensive gas station in the world.

While most wind tunnels test scale models, the "Cave of Winds" was large enough for actual airplanes.

Look closely and you’ll notice that the color changes a third of the way up the tower.

Architecture lovers won’t stop touching the National Gallery's 19.5 degree marble prow.

Members of Congress have traveled between the buildings on Capitol Hill for a century hidden from tourists, press, and storm clouds.

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

Those with a sharp eye can find the hidden image of a German Shepherd on the memorial's Mural Wall.

Home to items never before seen by the public.

If it hadn't been caught in time, a flaw in the design of this Manhattan skyscraper could have led to its collapse.

Stunningly detailed mosaics in a New York subway station bring life to the Weimaraners of artist William Wegman's work—and to thousands of commutes.

This study room in the New York Public Library saw the creation of one of contemporary America's greatest traitors.

An odd, ancient window that may have once been part of a brutal prison is embedded in the side of New York's Police Plaza.