Think you’re a master of local trivia? Try answering the Washingtology question of the day from Cultural Tourism DC. Take your best guess and see what others have answered in our daily quiz.

((Photo courtesy of Library of Congress))

Scroll down the page to find out the correct answer.

Answer: Listening for approaching aircraft

Source: “Historical image of large amplifiers being used to listen for approaching enemy aircraft. Photographed at the US Air Force base in Bolling Field, Washington DC, USA. Published in 1921.”

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