Environment Planet Earth 7 Towering Monadnocks Around the World By David DeFranza Updated April 19, 2021 Devil's Tower in Wyoming is both a culturally significant site for many Indigenous peoples and a popular rock climbing location. Stan Strange / EyeEm / Getty Images Share Twitter Pinterest Email Environment Weather Outdoors Conservation Mountains typically exist as part of a range or chain, with each peak sloping down and up into the next. Sometimes, however, erosion whittles away a mountain range and leaves a single rocky mass standing alone in the middle of an otherwise relatively flat plane. Unlike volcanoes, which rise upwards, monadnocks form when a core of hard rock resists erosion as the surrounding softer rock and soil is slowly carried away. What Is a Monadnock? A monadnock, also known as an inselberg, is an isolated, rocky ridge that is resistant to erosion and often surrounded by flat land. From Devil’s Tower in the Black Hills of Wyoming to Sugarloaf Mountain in Rio De Janeiro, here are seven stunning monadnocks around the world. 1 of 7 Mount Monadnock DenisTangneyJr / Getty Images The 3,165-foot-tall Mount Monadnock in southern New Hampshire rises high above the rest of the 1,017-acre Mount Monadnock State Park and the thousands of acres of protected land that lie beyond it. Interestingly, the elevated formation has an unnaturally low treeline due to repeated agricultural fires set by early settlers in the region. Mount Monadnock is a National Natural Landmark and features numerous popular hiking trails and a number of campsites. 2 of 7 Suilven Mountain lucentius / Getty Images In the Northwest Highlands of Scotland stands the three-peaked monadnock known as Suilven Mountain. The formation reaches a staggering 2,398 feet tall at its highest point, the summit of Caisteal Liath, or “Grey Castle” in Scottish Gaelic. In 2005, regional community members, along with the John Muir Trust, purchased the land on which Suilven Mountain sits in order to preserve the important natural landmark. 3 of 7 Devil’s Tower Reese Lassman / EyeEm / Getty Images 867 feet from its base to its summit, the remarkable Devil’s Tower in the Black Hills of northeastern Wyoming holds special meaning for many people. The most striking feature of the butte is its columnar jointing, with some columns reaching hundreds of feet high and 10 feet wide. What Is Columnar Jointing? Columnar jointing is when igneous rocks (rocks formed by lava or magma) begin to cool off into a solid form and start to contract. The contraction that occurs places stress on the rock and causes cracking, which results in hexagonal, column-like shapes. Devil’s Tower has special cultural and religious meaning for many different tribes of the region, including the Arapaho, Crow, Cheyenne, and Lakota, among several other Indigenous peoples. The location also happens to be a popular climbing spot, which has created conflict with those for whom it is sacred. 4 of 7 Hårteigen Petr Přindiš / Flickr / CC BY 2.0 Towering 1,570 feet above the plateau of Hardangervidda National Park in Sweden is the hat-shaped monadnock known as Hårteigen. Its vertical face makes it popular among experienced rock climbers and is typically considered a two-day climb. The gorgeous landscape surrounding Hårteigen is home to animals like the Arctic fox and snowy owl, and some of the largest wild reindeer herds in Europe. 5 of 7 The Big Pinnacle Jon Bilous / Getty Images The Big Pinnacle of Pilot Mountain, in North Carolina, stands 2,421 feet above sea level and is what’s left of the Sauratown Mountains. Sometimes referred to simply as “The Knob,” the monadnock features a predominant white cliff face that rises from a forested hill and is crowned by a wooded dome. The tree-topped summit has been closed to visitors since the 1970s and contains rare species of plants that include a flowering perennial called greenland sandwort, the threatened bear oak, and the endangered Appalachian golden banner. 6 of 7 Mulanje Massif Robert_Ford / Getty Images The Mulanje Massif in the southeast African country of Malawi is a monadnock large enough to change the weather. Rain clouds traveling inland from the coast are caught by the massif, whose peak towers 7,608 feet above the surrounding plains, and are forced to drop their water vapor. The Mulanje Massif is home to many noteworthy species of wildlife, like the endangered Mulanje cypress tree, the endangered bird Thyolo alethe, and numerous amphibian and lizard species, like the Mlanje Mountain chameleon. 7 of 7 Sugarloaf Mountain Cesar Okada / Getty Images Rising 1,299 feet up from the mouth of Guanabara Bay, the peak of Sugarloaf Mountain, or Pão de Açúcar in Portuguese, is visible from much of Rio de Janeiro, Brazil. The iconic monadnock, named after its conical shape reminiscent of molds once used to transport sugar, is fitted with a large cable car that famously carries visitors between its summit and a large hill called Morro da Urca. Sugarloaf Mountain became a UNESCO World Heritage Site in 2012.