Although the equestrian events at the 2012 Olympics have concluded, 55 horses remain on the Greenwich Park, London, grounds in preparation for this weekend’s men’s and women’s modern pentathlon competition.

Modern pentathlon is a competition comprised of five very different disciplines: fencing, swimming, horseback riding, shooting, and running. In the horseback riding portion athletes are tasked with completing a 12-jump, 1.30 meter (approximately 4-foot, 3-inch) jumping course on a horse they were randomly assigned to shortly prior to the competition. Each athlete has 20 minutes to get to know and warm up his or her mount for the jumping phase.

According to a recent report published on pentathlon.org, the official website of the International Union of Modern Pentathlon, "Ninety horses selected from top dealers (around Great Britain) have been whittled down to 40 competition horses and 15 training horses for the London 2012 Olympics. The process has included horse selection events where the horses were ridden by modern pentathletes on a similar surface and course to Greenwich Park."

The modern pentathlon horses arrived at Greenwich Park on Aug. 3, the report said, and during that time the horses’ owners have been familiarizing the animals to the surroundings. The report also noted that the pentathletes will have had four chances to ride leading up to the event