Engineering

This enormous storm barrier is one of the largest moving structures on Earth, with each arm taller than the Washington Monument.

This nine-story building is the oldest standing skyscraper in D.C.

The designer of this railway tunnel added a birthday present for himself.

The hidden offices underneath Memorial Bridge have been locked up since 1976.

This Victorian marvel of engineering and artistic prowess is nicknamed the "Cathedral of Steam."

The unique traffic pattern named for an influential urban planner is also known as the Pedestrian Scramble.

A working model of a pressure-driven, high-speed rail whizzes around a private vineyard.

An unusually designed bridge from the 1920s was built to withstand the tides and winds of Maine.

Fittingly, America's museum of architecture is itself a magnificently designed old building.

Before Nixon, "watergate" meant canals.

A magical work of architecture where a wind turbine enables monks to levitate.

This Gothic church was wheeled in its entirety to a new location a half a mile away.

100 years later, they're still down there.

A factory director designed what was the world's longest suspension footbridge in 1923 so his employees could get to work safely.

Camera cars and condom bikes built from scrap and one man's passion.