The world's longest outdoor covered escalator system transports commuters through Hong Kong's hilly terrain.

This playground sculpture of an icon from the past is dedicated to the children of the future.

Now a museum, once the site of the longest act of civil disobedience in United States history.

This unique Seattle structure was designed to be the greenest commercial building on the planet.

Allowing humans and fish alike to migrate from freshwater to saltwater and back again.

This massive World War II calculator hearkens back to the days when "computer" was a job title.

Impossibly life-like natural history models created out of glass by a father and son.

This peaceful Massachusetts graveyard was one of the first "garden-style" cemeteries in America.

Three prestigious academic collections come together to create a world-class natural history museum.

This electronics repair store celebrates the history of computers.

The world's largest piece of copyrighted artwork.

A metal menagerie fills the yard of this museum and gallery, the work of Montana artist Bill Ohrmann.

Soaring over the Niagara Whirlpool since 1916.

An outsider art duo's yard has been turned into a whimsical public gallery.

The largest Walmart Supercenter in the United States, referred to affectionately as “Mallmart,” has served the residents of Albany, New York, since 1994.

Two thousand artifacts from around the world collected by one woman who loved to travel.

An enormous, inside-out glass globe built in 1935.

No one really knows how these old hobby horses got here, but the herd keeps growing.

A historic bridge with a lovely acoustic anomaly.

The oldest philatelic museum in the United States.

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.

Outdoor exhibits explore the contributions of European, African, and indigenous peoples to American frontier culture.

A railroad tunnel that, upon its completion, was considered one of the engineering marvels of the modern world.

The story behind the mysterious symbol painted in front of the historic university's famous Rotunda.