Jan 31 (Reuters) - Here are the main facts about bobsleigh at the Sochi Winter Olympics.
There are three gold medals up for grabs in the men's four-man, two-man and two-woman events.
The competition consists of four runs held over a two-day period. Medals are awarded based on the total time over the four runs, with the winner having the lowest overall time. If two teams complete the competition in a tie, they are awarded the same place.
Bobsleigh has been contested at the Winter Olympic Games since the first Winter Games in 1924 in Chamonix, France, with the exception of the 1960 showpiece in Squaw Valley, California, where there was no track.
The two-woman event was introduced at Salt Lake City in 2002.
Germany and Switzerland are the traditional powerhouses in men's bobsleigh with the former having won seven of the 10 golds at the last five Games.
In women's bobsleigh, the three golds since the event was introduced have gone to the United States, Germany and Canada four years ago.
The Olympic track at the Sanki Sliding Centre winds its way across the northern slope of the Aibga Ridge with a finishing area located in Rzhanaya Polyana. The overall length of the track is 1.814 metres, 314 of which are taken up by the braking area.
There are 17 curves with a vertical drop of 132m from top to bottom, with its highest point being located at 836m above sea level and its lowest point at 704m.
There are three negative slopes to slow competitors down - with safety as the primary concern following the death of Georgian luger Nodar Kumaritashvili during a training run at the 2010 Winter Olympics in Vancouver.
American Steve Holcomb defends his four-man title but faces tough opposition from Germany's Maximilian Arndt and Russian Alexander Zubkov.
Holcomb has enjoyed a better season in the two-man sled with Zubkov, Switzerland's Beat Hefti and Germany's Thomas Florschuetz also set to do battle for the podium.
The battle for women's bobsleigh gold appears to be between Canada's defending champion Kaillie Humphries, any one of the three American teams and Germany. (Compiled by Justin Palmer; Editing by Julien Pretot)