Three-day eventing is an extreme test of all-round ability of both horse and rider, having been likened to an 'equine triathalon'. The sport evolved from the requirements for a top class military charger – steadiness and elegance on parade, the ability to gallop across country in battle, and then to continue with duties after a strenuous day. These requirements have transformed in to the three modern phases of the sport – Dressage, Cross-Country and Show Jumping.