A dressage arena is marked around the edge with letters and many riding schools also use these letters around a riding arena or manege. These letters are used during a dressage test or riding lesson to instruct the rider when to perform different movements such as to ride a circle, change the rein, change the gait, etc.
A standard dressage arena is 20 metres by 40 metres and 11 letters are used: 8 letters around the edge and 3 invisible letters along the centre line of the arena. A long dressage arena is 20 metres by 60 metres and 17 letters are used: 12 around the edge of the arena and 5 invisible letters along the centre line of the arena.
Although riding maneges at riding schools and livery yards may vary from the standard dressage arena sizes, many still use letters around the arena to issue instructions to a rider during a lesson.
The images below show the location of the letters that denote a particular point in 20m x 40m dressage arena and 20m x 60m dressage arena. These images show both the physical markers around the edge of the arena, and the internal letters that need to be memorised.
20m x 40m Arena
20m x 60m Arena