It's about nine-tenths as big as The Lincoln Memorial Reflecting Pool.
In other words, 28 dunams is 0.889 times the size of The Lincoln Memorial Reflecting Pool, and the size of The Lincoln Memorial Reflecting Pool is 1.12 times that amount.(Washington, D.C.) (pool surface area)
It's about one-and-three-fifths times as big as The Kennedy Center.
In other words, the size of The Kennedy Center is 0.63 times 28 dunams.(a.k.a. John F. Kennedy Memorial Center for the Performing Arts) (Washington, DC)
Hosting over 2,000 performances and nearly two million audience members annually — including events and guests for presidential inaugurations and galas — the Kennedy Center is approximately 17 dunams in total area.
It's about one-and-seven-tenths times as big as The Biltmore Estate.
In other words, 28 dunams is 1.72 times the size of The Biltmore Estate, and the size of The Biltmore Estate is 0.581 times that amount.(Asheville, North Carolina) (house only)
It's about three-fifths as big as a Polo field.
In other words, 28 dunams is 0.558128688 times the size of a Polo field, and the size of a Polo field is 1.79170149 times that amount.(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 50.1676416 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 half as big as Windsor Castle.
In other words, 28 dunams is 0.53 times the size of Windsor Castle, and the size of Windsor Castle is 1.9 times that amount.(Windsor, England) (total site area)
It's about one-and-nine-tenths times as big as The Great Banyan Tree.
In other words, 28 dunams is 1.94 times the size of The Great Banyan Tree, and the size of The Great Banyan Tree is 0.515 times that amount.(a.k.a. The Great Banyan, a.k.a. Ficus benghalensis) (Acharya Jagadish Chandra Bose Indian Botanic Garden, Howrah, West Bengal, India)
It's about one-third as big as Buckingham Palace.
In other words, the size of Buckingham Palace is 2.8 times 28 dunams.(a.k.a. Buckingham House) (Westminster, London, England)