The David E. Grange Jr. Best Ranger Competition will kick off Friday at Fort Benning, Georgia.

The storied and famously tough three-day competition pits two-man teams against each other in back-to-back events. The winning duo will earn the title of Best Ranger.

So far, as many as 51 teams have signed up to compete in this year's competition, which is hosted by the Airborne and Ranger Training Brigade.

Units slated to participate this year include the 82nd Airborne Division, the Army National Guard, the 25th Infantry Division, the 10th Mountain Division and the 75th Ranger Regiment.

Competitors, who must be graduates of the Army Ranger School, are put through events that test their physical conditioning, Ranger skills and team strategies. The events are back-to-back and around the clock for 60 hours, allowing little time for rest and meals.

In the past, events included weapons firing, extended road marches, day and night land navigation courses, Ranger skills and parachute jumps. All events are timed, and competitors score points for each completed event. Both team members must complete each task.

The Best Ranger Competition was established in 1982 and has been compared to Ironman and Eco-Challenge competitions.

Last year, only 26 of the 50 teams to begin the competition made it into the final day. Of the 50 teams at the starting line in 2013, only 23 finished the competition. And in 2012, 34 of the 50 teams completed the competition.

This year's competition will begin at 6 a.m. on Friday; organizers estimate the competition will wrap up about 4 p.m. Sunday.

A formal awards ceremony is scheduled for 10 a.m. April 13 at McGinnis-Wickam Hall in Fort Benning's Marshall Auditorium.

The competition is open to the public. A schedule of events will be released to the public on Wednesday on the Fort Benning Facebook page. Family, friends and spectators are encouraged to tweet updates on their teams during the competition using the hashtag #2015Best Ranger, @Fort Benning.