It's about as big as The Pentagon.
(a.k.a. United States Department of Defense Headquarters) (Washington, D.C.) (total floor area)
The Pentagon, the world's largest office building, contains a total floor area of 138 dunams. Built during World War II, the designers compensated for the steel rations then in effect by using 310,000 cu. m of concrete in the construction efforts.
It's about one-and-one-fourth times as big as Ellis Island.
In other words, 138 dunams is 1.240 times the size of Ellis Island, and the size of Ellis Island is 0.8060 times that amount.(Jersey City, New Jersey and New York City, New York)(now officially part of the Statue of Liberty National Monument)
Ellis Island, home of the Ellis Island Immigration Station, is 111 dunams in total area. Nine-tenths of the island were artificially created after the New York-New Jersey borders had already been defined, leading to a sovereignty dispute which was settled by the US Supreme Court in 1998.
It's about seven-tenths as big as Grand Central Station.
In other words, the size of Grand Central Station is 1 times 138 dunams.(formally Grand Central Terminal, a.k.a. Grand Central, a.k.a. GCT) (New York City, New York) (total terminal area). Grand Central station, the largest train station in the world by platform count, measures 200 dunams in total area. The large flag which was suspended from the concourse ceiling following the September 11th 2001 terrorist attacks measures about 0.07 dunams.
It's about one-and-three-fifths times as big as Alcatraz.
In other words, the size of Alcatraz is 0.630 times 138 dunams.(a.k.a. The Rock) (California)
Alcatraz Island measures 89 dunams. It is known a part of the Golden Gate National Recreation Area, and has historically served as a lighthouse, fort, military prison, and — most famously — a federal prison.
It's about three-fifths as big as Washington National Cathedral.
In other words, the size of Washington National Cathedral is 1.70 times 138 dunams.(a.k.a. Cathedral Church of Saint Peter and Saint Paul) (Washington, DC) (total plot)
Sitting atop the 115 m (377 ft) tall Mount Saint Alban at the corner of Massachusetts and Wisconsin Avenues, Washington National Cathedral sits on a landscaped, 230 dunams plot.
It's about three-fifths as big as The United States Capitol.
In other words, the size of The United States Capitol is 1.70 times 138 dunams.(Washington, DC) (Immediate grounds size)
The grounds of United States Capitol, at the center of Washington DC's quadrants, consists of about seventeen buildings on a 230 dunams plot. While the Capitol Building is the central feature, other buildings include the Supreme Court Buildings and the Library of Congress Buildings, as well as several monuments and sculptures.
It's about one-and-four-fifths times as big as Buckingham Palace.
In other words, the size of Buckingham Palace is 0.560 times 138 dunams.(a.k.a. Buckingham House) (Westminster, London, England)
Buckingham Palace, the official residence of the British monarch, contains about 77 dunams of total floor space. The palace was first inhabited by Queen Victoria in 1831, although after the death of her husband in 1861, the Queen endeavored to spend as little time there as public opinion would allow.