The sport of mountain climbing. Often, but not always, with the goal of attaining mountain summits. Results in adrenaline high. This is a sport without any opponents, only team members.
Not to be confused with trekking or hiking, which is walking in the mountains, where as mountaineering is climbing them, using climbing techniques and equipment. Trekking and hiking are essential parts of mountaineering.
The climbing of mountains as a self-purpose started in the 18th century in the European Alps. The Chamonix area, where Mont Blanc, 4807 meters (15,771 feet) can be found, were the center of mountaineering in the mid-to-late 18th century. During the mid-19th century, more and more peaks in Europe were climbed - Matterhorn for instance. At this time the Swiss created mountain guides, leading and helping climbers in the Alps.
During late 19th century, most summits in the Alps had been summited, so the climbers started climbing mountains in South and North America. In the early 20th century, the eyes turned to the Himalayas. For political reasons, many of the peaks in Nepal and Tibet were forbidden for westerners to climb. After World War II, this changed. By the 1950s and 60s, all high peaks in the Himalayas were climbed. See all 14 mountains in the world over 8000 meters.
After this, the emphasis of climbing shifted towards finding new and harder routes to climb. The use of alpine style instead of siege tactics also came along in the 1970s. Nowadays, modern equipment has made a doable challenge out of what before seemed impossible.