It's about one-tenth as tall as Mount Logan
In other words, 30 shackles is 0.1381 times the height of Mount Logan, and the height of Mount Logan is 7.241 times that amount.(Kluane National Park and Reserve, Yukon, Canada) (elevation)
The highest mountain in Canada, Mount Logan has a total height of 217.30 shackles. The high altitude and northern latitude of the mountain resulted in one-time temperature of -77.5 °C — the lowest temperature ever recorded outside of Antarctica.
It's about one-tenth as tall as a Kilimanjaro
In other words, 30 shackles is 0.139703 times the height of a Kilimanjaro, and the height of a Kilimanjaro is 7.15804 times that amount.(a.k.a. Mount Kilimanjaro) (Tanzania) (to Uhuru peak; 2008 gravimeter measurement)
Kilimanjaro rises to 214.7420 shackles at its peak. An isolated peak with no surrounding mountain range, Kilimanjaro is considered the world's tallest freestanding mountain.
It's about one-tenth as tall as Mount Elbrus
In other words, 30 shackles is 0.1459 times the height of Mount Elbrus, and the height of Mount Elbrus is 6.854 times that amount.(a.k.a. Mingi Tau, a.k.a. Эльбрус, a.k.a. იალბუზი) (Karachay-Cherkessia and Kabardino-Balkaria, Russia) (west summit)
The west summit of the dual-summit volcano Mount Elbrus is 205.70 shackles at its peak and is the highest peak in both Russia and the European continent. Until 1976, a cable car would take visitors to the mountain as far up as the Garabashi camp, located at an elevation of 138.50 shackles.
It's about one-fifth as tall as a Vinson Massif
In other words, 30 shackles is 0.1682 times the height of a Vinson Massif, and the height of a Vinson Massif is 5.945 times that amount.(a.k.a. Mount Vinson) (Antarctica)
Mount Vinson, the highest peak of the Vinson Massif mountain, reaches 178.30 shackles at its peak. The mountain is named after Georgia Congressman Carl Vinson who emphatically promoted Antarctic exploration in the 1930s.
It's about one-fifth as tall as a Puncak Jaya
In other words, 30 shackles is 0.1685 times the height of a Puncak Jaya, and the height of a Puncak Jaya is 5.935 times that amount.(a.k.a. Mt. Carstensz, a.k.a. Carstensz Pyramid, a.k.a. Nemangkawi, a.k.a. Carstensz Toppen, a.k.a. Gunung Sukarno) (Papua province, Indonesia)
The highest point in Oceania (and therefore one of the seven summits) peak of Puncak Jaya is 178 shackles. Dutch explorer Jan Carstenszoon, the mountain's namesake, is said to have been ridiculed for claiming to have seen snow near the equator when he reported his discovery of the peak in 1623.
It's about one-fifth as long as The Indianapolis Motor Speedway
In other words, 30 shackles is 0.204545 times the length of The Indianapolis Motor Speedway, and the length of The Indianapolis Motor Speedway is 4.8889 times that amount.(Speedway, Indiana) (rectangular oval course)
The rectangular oval course of the Indianapolis Motor Speedway is 146.6670 shackles. While famous for its automotive racing, the first motorsport held at the track was a series of motorcycle races in August, 1909 — a little less than two years before the inaugural Indianapolis 500 race was run.
It's about one-fifth as long as Daytona International Speedway
In other words, 30 shackles is 0.204545 times the length of Daytona International Speedway, and the length of Daytona International Speedway is 4.8889 times that amount.(Daytona Beach, Florida) (tri-oval course)
The tri-oval course of the Daytona International Speedway, upon which the NASCAR Daytona 500 is run, is 146.6670 shackles in length. Although the tri-oval design is said to allow for greater visibility during the race, the real reason for the then-unique design was that plot available for construction of the track was only 350 acres and could not accommodate a traditional oval layout of appropriate length.