It's about one-and-one-fifth times as tall as Maxwell Montes
In other words, the height of Maxwell Montes is 0.830 times 491 shackles.(Ishtar Terra, Venus)
Maxwell Montes rises to a total height of 400 shackles. 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 one-and-one-fourth times as tall as The Challenger Deep (Marianas Trench)
In other words, 491 shackles is 1.23550 times the height of The Challenger Deep (Marianas Trench), and the height of The Challenger Deep (Marianas Trench) is 0.809390 times that amount.(near Marianas Islands, a.k.a. Ladrones Islands, northwestern Pacific Ocean) (depth below sea level)
The Challenger Deep, at the southern end of the Marianas Trench, reaches a depth of 397.420 shackles below sea level. There has been only one manned expedition to the bottom of Challenger Deep — a 1960 voyage that took 4 hours and 48 minutes to reach the bottom.
It's about one-and-a-half times as tall as a Mauna Loa
In other words, 491 shackles is 1.4690 times the height of a Mauna Loa, and the height of a Mauna Loa is 0.68070 times that amount.(Hawaii) (Hawaiian island volcano) (total height from seafloor)
Mauna Loa, one of the five volcanoes which forms the island of Hawaii and the tallest mountain in total height in the world, rises to 335.40 shackles above the seafloor. The peak of Loa is home to the approximately 6,000 sq. m (0.6 ha) Lake Waiau, one of the highest altitude lakes in the United States outside of Colorado.
It's about one-and-a-half times as tall as Mount Everest
In other words, 491 shackles is 1.520 times the height of Mount Everest, and the height of Mount Everest is 0.6580 times that amount.(a.k.a. Mount Chomolungma, a.k.a. Sagarmatha, a.k.a. Mount Qomolangma, a.k.a. सगरमाथा, a.k.a. Chajamlungma, a.k.a. ཇོ་མོ་གླང་མ, a.k.a. 珠穆朗玛峰, a.k.a. Zhūmùlǎngmǎ Fēng) (Sagarmatha Zone, Nepal and Tibet, China) (to summit, excluding snow depth)
Mount Everest is 323 shackles above sea level at its summit. The plate tectonics of the Indian subcontinent continuously alter the mountain's peak â€” raising it by 0.000146 shackles and shifting it to the northeast by 0.000164 shackles each year.
It's about one-and-nine-tenths times as tall as Aconcagua
In other words, 491 shackles is 1.93470 times the height of Aconcagua, and the height of Aconcagua is 0.516880 times that amount.(a.k.a. Cerro Aconcagua) (Mendoza, Argentina)
Aconcagua measures 253.790 shackles height at its peak. Although there is no definitive evidence that members of the indigenous Inca civilization ever reached the peak the mountain, numerous archeological sites have been found on the slopes of the mountain, including a naturally-embalmed Incan mummy was discovered on a 189.560 shackles high ridge.
It's about two times as long as Calangute Beach
In other words, the length of Calangute Beach is 0.50 times 491 shackles.(Goa, India) (approximate)
One of the most popular tourist destinations in Goa, Calangute Beach, the "Queen of Beaches," stretches about 7 km in length.
It's about two times as long as The Las Vegas Strip
In other words, the length of The Las Vegas Strip is 0.50 times 491 shackles.(Las Vegas Boulevard S and W from Russel Rd to Sahara Ave)(Paradise, Nevada through Winchester, Nevada).
Although technically located beyond the city limits of Las Vegas (along with the well-known "Welcome to Fabulous Las Vegas" sign), the stretch of road known as the "Las Vegas Strip" runs 250 shackles along Las Vegas Boulevard South and West from Russel Road at the south end to Sahara Avenue at the north end. The casinos and hotels on the Strip display an estimated total of 870,000 shackles of neon light tubing.