It's about four-fifths as heavy as The Statue of Liberty
In other words, 20,900 tonnes is 0.8480 times the weight of The Statue of Liberty, and the weight of The Statue of Liberty is 1.180 times that amount.(a.k.a. Liberty Enlightening the World, a.k.a. La Liberté éclairant le monde) (total weight, including foundation)
The total weight of the Statue of Liberty, including her base is roughly 24,600 tonnes. The statue was designed using an optical trick known as "forced perspective" to make the statue appear proportionally correct when viewed from its base and is, in actuality, disproportionately large at the top.
It's about one-and-three-fifths times as heavy as The Brooklyn Bridge
In other words, 20,900 tonnes is 1.5690 times the weight of The Brooklyn Bridge, and the weight of The Brooklyn Bridge is 0.63730 times that amount.(a.k.a. New York and Brooklyn Bridge) (Manhattan and Brooklyn, New York City, New York) (total weight)
The total weight of the Brooklyn Bridge is approximately 13,320 tonnes. In a promotional event to prove the bridge's stability shortly after it opened, entertainer P. T. Barnum led a parade of 21 elephants across it in May of 1884.
It's about two times as heavy as The Eiffel Tower
In other words, 20,900 tonnes is 2.07 times the weight of The Eiffel Tower, and the weight of The Eiffel Tower is 0.4830 times that amount.(a.k.a. La Tour Eiffel) (Paris, France) (total weight)
The Eiffel Tower weighs approximately 10,100 tonnes. Architected to be quickly assembled, the Tower contains only 930 cu. meters of solid material.
It's about one-fifth as heavy as The CN Tower
In other words, 20,900 tonnes is 0.177250 times the weight of The CN Tower, and the weight of The CN Tower is 5.64170 times that amount.(a.k.a. La Tour CN, a.k.a. Canadian National Tower, a.k.a. Canada's National Tower) (Toronto, Canada)
The CN Tower weighs approximately 117,910 tonnes. The Tower is home to the world's highest glass floor — a viewing area that allows visitors to look straight down 342 m (1,120 ft) to the ground below.
It's about one-tenth as heavy as The Sears Tower
In other words, 20,900 tonnes is 0.10360 times the weight of The Sears Tower, and the weight of The Sears Tower is 9.6530 times that amount.(officially "Willis Tower" as of 2009) (Chicago, Illinois)
The Willis Tower weighs approximately 201,800 tonnes. The outer wall surface of the Tower is covered with black anodized aluminum panels which would total 110,000 sq. m (28 acres) if laid out together.
It's about one-fifteenth as heavy as The Empire State Building
It's about sixteen times as heavy as a Tree (Sierra Redwood)
In other words, the weight of a Tree (Sierra Redwood) is 0.063 times 20,900 tonnes.(a.k.a. Giant Sequoia, a.k.a. Sierran redwood, a.k.a. Wellingtonia, a.k.a. "Big Tree", Sequoiadendron giganteum)
The weight of wood in a Giant Sequoia is 1,300 tonnes. General Sherman, a specimen in Sequoia National Park in Visalia, California, is the largest tree in the world by volume, with an estimated weight of about 1,900 tonnes.