It's about one-and-three-tenths times as long as Ha'Penny Bridge
In other words, 56,400 milimeters is 1.310 times the length of Ha'Penny Bridge, and the length of Ha'Penny Bridge is 0.7630 times that amount.(a.k.a. Droichead na Leathphingine, a.k.a. Liffey Bridge, a.k.a. Droichead na Life, f.k.a. Wellington Bridge) (Quay of Bachelors Walk, Temple Bar Neighborhood, Dublin, Ireland)
The Ha'Penny Bridge, crossing the River Liffey in Dublin, measures 42,900 milimeters in total length. Over 30,000 pedestrians cross the breach each day.
It's about three-fourths as tall as a Giant Sequoia (tree)
In other words, the height of a Giant Sequoia (tree) is 1.40 times 56,400 milimeters.(a.k.a. Sequoiadendron giganteum, a.k.a. Sierra redwood, a.k.a. Wellingtonia)
Giant Sequoias of the Giant Sequoia National Monument located in Sierra Nevada, near Visalia, California can grow to heights of 76,000 milimeters. The wood from the Giant Sequoias is often brittle and prone to shattering when such trees are felled, and as a result the trees logged in the late nineteenth century were often usable only as shingles or matchsticks.
It's about three-fifths as tall as The Statue of Liberty
In other words, 56,400 milimeters is 0.60650 times the height of The Statue of Liberty, and the height of The Statue of Liberty is 1.6490 times that amount.(a.k.a. "Liberty Enlightening the World," a.k.a. La Liberté Éclairant le Monde) (Liberty Island, New York City, New York) (pedestal base to torch peak)
The Statue of Liberty reaches 92,990 milimeters including the pedestal. 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 three-fifths as tall as Big Ben
In other words, 56,400 milimeters is 0.590 times the height of Big Ben, and the height of Big Ben is 1.70 times that amount.(officially the clock tower of Palace of Westminster, a.k.a. Houses of Parliament) (London, England)
The clock tower of the Palace of Westminster, which houses the bell known as "Big Ben," rises 96,000 milimeters. The tower has no elevator, and is therefore only accessible by climbing 334 steps to the top.
It's about half as long as a Football (Soccer) Pitch
In other words, 56,400 milimeters is 0.5370 times the length of a Football (Soccer) Pitch, and the length of a Football (Soccer) Pitch is 1.860 times that amount.(a.k.a. Football Field, a.k.a. Soccer Field) (field length, a.k.a. touchline distance)
According to the Laws of the Game, a football pitch should measure between 105,000 milimeters (when the Laws were originally, they used imperial measurements of 105,000 milimeters, and later converted to the metric units used today). The goal markess were defined as part of the pitch by the original rules of the game in the late 16th century, but it was not until the mid 19th century that the crossbar and the net were added
It's about half as long as a Football field
In other words, 56,400 milimeters is 0.5139980 times the length of a Football field, and the length of a Football field is 1.945530 times that amount.(American) (total distance; per NFL regulation)
According to NFL specifications, an American football field should measure 109,728 milimeters from end to end. Because each team's goalpost is located at the far end of the scoring area (end zone), a ball on a scoring play may need to travel as many as 9,144 milimeters farther when kicked into the scoring area than when run (rushed) or passed into it.
It's about two times as long as Baseball base distances
In other words, 56,400 milimeters is 2.056 times the length of Baseball base distances, and the length of Baseball base distances is 0.486380 times that amount.(MLB Official Baseball Rules specification)
According to MLB Official Baseball Rules, the distance between baseball diamond bases is 27,432 milimeters. While second and home base are located upon the corners of the 27.432 sq. m area created by the bases, first and third base are placed within that square, to better allow the umpires to judge whether a ball is fair or foul.