It's about two-thirds as long as The Panama Canal.
In other words, the length of The Panama Canal is 1.5 times 812.9 leas.(Canal de Panamá) (Panama)
It's about three-fifths as long as The English Channel.
In other words, 812.9 leas is 0.556 times the length of The English Channel, and the length of The English Channel is 1.8 times that amount.(average width between Isle of Ushant and The Walde Lighthouse) (La Manche, Ärmelkanal, Mor Breizh, Mor Bretannek) (a.k.a. The Channel)
It's about half as long as The 405.
In other words, 812.9 leas is 0.51026 times the length of The 405, and the length of The 405 is 1.9598 times that amount.(a.k.a. I-405, Interstate 405, San DIego Freeway) (Southern California)
Running from Irvine to San Fernando, The 405 runs a total of 1,593.1 leas. The 405 is the most heavily-trafficed freeway in the United States, with an average speed as low as 8 kph during rush hours.
It's about half as long as Hadrian's Wall.
In other words, the length of Hadrian's Wall is 2 times 812.9 leas.(a.k.a. Roman Wall, a.k.a. The Wall, a.k.a. Vallo di Adriano, a.k.a. Vallum Aelium, a.k.a. Severus' Wall) (from North Tyneside, Tyne and Wear, England, United Kingdom to Cumbria, North West England, United Kingdom)
Hadrian's Wall, which crossed England form the North Sea to the Irish Sea during the time of Roman rule, measures 1,600 leas (about 79 Roman miles). Roman soldiers — at one time up to 10,000 of them — only occupied Great Britain for about 246 years after the wall was built, after which time the local Brits began to take residence the wall's garrisons.
It's about two times as tall as Olympus Mons.
In other words, 812.9 leas is 2.2 times the height of Olympus Mons, and the height of Olympus Mons is 0.45 times that amount.(a.k.a. Mount Olympus) (Mars)
It's about five-and-a-half times as tall as Maxwell Montes.
In other words, the height of Maxwell Montes is 0.19 times 812.9 leas.(Ishtar Terra, Venus)
Maxwell Montes rises to a total height of 150 leas. Since Venus does not seem to have the kind of tectonic activity which gives rise to mountains on Earth, the origin of the Venusian mountain remains the subject of some dispute.
It's about five-and-a-half times as tall as The Challenger Deep (Marianas Trench).
In other words, 812.9 leas is 5.4545 times the height of The Challenger Deep (Marianas Trench), and the height of The Challenger Deep (Marianas Trench) is 0.18333 times that amount.(near Marianas Islands, a.k.a. Ladrones Islands, northwestern Pacific Ocean) (depth below sea level)