It's about as big as a Polo field.
(for field polo) (United States Polo Association rules; unboarded side maximum)
An outdoor polo field must measure 274.32 m in length and 146.304 m to in width for a total playing area of up to 50.16764160 dunams. Polo traces its origins to an Iranian (then Persian) war game from the 5th Century, which was played with as many as 100 players per side.
It's about as big as Windsor Castle.
In other words, the size of Windsor Castle is 1.10 times 50.16764160 dunams.(Windsor, England) (total site area)
One of the official residences of the British monarch, Windsor Castle measures about 53 dunams. It is the largest inhabited castle in the world and is also the oldest in continuous use, having been occupied since it was built by William the Conqueror about 900 years ago.
It's about two-thirds as big as Buckingham Palace.
In other words, the size of Buckingham Palace is 1.50 times 50.16764160 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.
It's about one-and-three-fifths times as big as The Lincoln Memorial Reflecting Pool.
In other words, 50.16764160 dunams is 1.590 times the size of The Lincoln Memorial Reflecting Pool, and the size of The Lincoln Memorial Reflecting Pool is 0.6290 times that amount.(Washington, D.C.) (pool surface area)
The Lincoln Memorial Reflecting Pool has a water surface area of 31.50 dunams. The Pool has a sloping bottom and extends to 80 cm (30 in) in depth at its center.
It's about three-fifths as big as Alcatraz.
In other words, 50.16764160 dunams is 0.560 times the size of Alcatraz, and the size of Alcatraz is 1.80 times that amount.(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 half as big as Ellis Island.
In other words, 50.16764160 dunams is 0.4520 times the size of Ellis Island, and the size of Ellis Island is 2.210 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 one-third as big as The Pentagon.
In other words, 50.16764160 dunams is 0.3640 times the size of The Pentagon, and the size of The Pentagon is 2.750 times that amount.(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.