Dressage is occasionally referred to as "Horse Ballet."this discipline has ancient roots in Europe, dressage was first recognized as an important equestrian pursuit during the Renaissance. European riding masters of that period developed a sequential training system that has changed little since then. Classical dressage is still considered the basis of modern dressage.
In a dressage competition all levels are demonstrated through a series of tests where the horse will do a variety of different movements within a standard arena.
Judges evaluate each movement on the basis of an objective standard appropriate to the level of the test and assign each movement a score from zero to ten – zero being "not executed" and 10 being "excellent". A score of 9 is very good and is a high mark, while a competitor achieving all 6s (or 60% overall) should be considering moving on to the next level.
Two sizes of arenas are used small and standard and each has letters assigned to positions around the arena for dressage tests to specify where movements are to be performed.
Cones with letters on them are positioned on the edge of the arena to indicate where a movement is to performed.
The small arena is 20m by 40m (66 x 131 ft) the letter being , and is used for the lower levels of eventing in the dressage phase.
The standard dressage arena letters are A-K-V-E-S-H-C-M-R-B-P-F the small size arena has A-K-E-H-K-M-B-F.
The dressage arena also has a centerline (from A to C, going through X in the middle), as well as two quarter-lines (halfway between the centerline and long sides of each arena).