The Transantarctic Mountains (abbreviated TAM) comprise a mountain range of uplifted rock (primarily sedimentary) in Antarctica which extends, with some interruptions, across the continent from Cape Adare in northern Victoria Land to Coats Land. These mountains divide East Antarctica and West Antarctica. They include a number of separately named mountain groups, which are often again subdivided into smaller ranges.
The range was first sighted by James Clark Ross in 1841 at what was later named the Ross Ice Shelf in his honour. It was first crossed during the British National Antarctic Expedition of 1901-1904.