The Event
The event consists of three phases, the acronyms of which still bear their French lineage. Points are accrued for each phase, the winner being the individual with the highest accumulated score (maximum points = 460) over the three phases:

POR (Le Parcours d'Orientation et de Régularité). An optimum speed and orienteering course testing the rider’s ability to navigate accurately. During this stage you will be given a route marked on a map that you must follow accurately. Checkpoints will be encountered at random on the route and you will be set speeds at which to cover the ground between checkpoints of between 6 – 12 kms (3 ¾ - 7 ½ mph), which a horse can comfortably do at walk and trot. 240 points are available and you lose one point for each minute you are over or under the optimum time at each checkpoint.
CG (La maîtrise des allures) Control of Gaits. This phase simulates the need for a horse to maintain either a fast walk or hand canter over distance without tiring. It is a little contrived as the test consists of two legs: cantering 150m in a straight line then retracing the same course at walk, furthermore the hand canter has become quite a collected canter, however with a little practice both are achievable. Only 60 points available here, 30 each way. The marking zones are between 26.3 and 33.8 seconds to score for the canter and between 97 and 67 seconds for the walk. If the pace is broken on either leg then all points for that leg are lost.
PTV (Le Parcours en Terrain Varié). A timed “cross-county” course of up to 5 kms and containing 16 obstacles. This phase tests the combination over obstacles that would be encountered naturally whilst in the countryside. The rule book lists 26 varieties which involve activities such as:
Riding / leading up / down inclines, steps, banks, staircase or bridges.
Jumping a log / ditch / hedge.
A course of bending poles, crossing water, riding under low branches.
Mounting (either side), immobility, loading into a trailer
160 points are available for this phase, 10 per obstacle. The beauty of TREC is that no obstacles are compulsory, however if you chose to omit one or more you will lose the 10 points associated with each.