For dressage, an arena is laid out strictly and must be exact.
The arena is used for the different manoeuvres in the sport and
each one must be completed at the right points. Therefore, there
can be no variation in the layout as riders would not know what
to expect. The standard arena is 20m by 40m but longer arenas at
60m are used for higher standards of rider. The LettersThe
dressage arena is lettered around the edge and in the middle so
that the rider can pick out where they have to perform each
movement or where they must start from. There are usually
markers around the edge, but the letters in the middle are not
marked and therefore the rider must learn by heart where they
are. The letters start with A which denotes the entrance to the
arena. A is in the middle of one of the two shorter sides of the
arena. Directly opposite A, in the middle of the other shorter
side is C. The judges sit behind C. Across the top, one of the
long ends; there are K, E and H (assuming A is on the left of a
plan). On the long