It's about as big as The Mall of America.
It's about nine-tenths as big as Vatican City.
In other words, 390 dunams is 0.890 times the size of Vatican City, and the size of Vatican City is 1.10 times that amount.(a.k.a. Holy See, a.k.a. State of the Vatican City, a.k.a. Stato della Città del Vaticano)
The world's smallest nation in both area and population, Vatican City is a walled enclave within Rome, Italy measuring 440 dunams in total area. Vatican City has been home to the Papacy since its incorporation in 1929 and the territory has been the home of Popes since 1377.
It's about three-fifths as big as Disneyland.
In other words, the size of Disneyland is 1.70 times 390 dunams.(a.k.a. Disneyland Park) (Anaheim, California) (public areas)
The public areas of Disneyland occupy 650 dunams. The park consists of nine themed "stages" — including Main Street, U.S.A; Adventureland; Frontierland; Fantasyland; and Tomorrowland — with hidden passages that allow park employees to move between each without being seen by guests.
It's about one-and-seven-tenths times as big as Washington National Cathedral.
In other words, the size of Washington National Cathedral is 0.590 times 390 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 one-and-seven-tenths times as big as The United States Capitol.
In other words, the size of The United States Capitol is 0.590 times 390 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 half as big as The Forbidden City.
In other words, 390 dunams is 0.530 times the size of The Forbidden City, and the size of The Forbidden City is 1.90 times that amount.(a.k.a. Forbidden Palace, a.k.a. Purple Forbidden City, a.k.a. Zijin Cheng, a.k.a. Zǐjinchéng, a.k.a. 紫禁城) (Beijing, China)
The imperial palace complex of the Forbidden City consists of 980 buildings covering 740 dunams. The City was the home of Chinese Emperors and their cabinets from its construction in 1420 until the fall of the last ruling dynasty in 1912.
It's about two times as big as Grand Central Station.
In other words, the size of Grand Central Station is 0.50 times 390 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.