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20 meter circles

The first, and arguably the easiest, circle to ride in dressage tests is the 20m circle. This movement is required through Second Level in U.S. dressage tests and is performed at the trot and canter.

Circles are supposed to be round, which means the horse turns the same amount at each stride. This is harder than it sounds, especially if your horse is plagued by "rail magnets": once he's on the rail he doesn't want to come off! There should be no straight lines or corners involved in riding circles. At those points of the circle which are tangent to the rail, the horse should take only one or two steps on the rail before leaving it to follow the track of the circle.

20 meter circles large arena

Look at the diagram above. You can see that in the large arena, which is 20 meters wide and 60 meters long (check your arena diagrams if you're unsure of the arena dimensions), there is room for 3 separate 20m circles.

When riding a 20 meter circle which begins and ends at C or A, you should leave the rail as you pass the letter. (Some people say you're "at" the letter when your horse's shoulder is next to the letter; others say you're at the letter when your body passes it. It's a pretty fine point -- probably either will work. Just be consistent.)

As you continue on the circle, you'll touch the rail at a point 10 meters from the end of the arena (hurray for circle points!). If your circle begins at B or E, you touch the rail for a moment at each of these letters before continuing on the circle.

Remember that the corner letters (M, F, H, K) are only 6 meters from the end of the ring. When riding 20 meter circles at A or C, you need to touch the rail 4 meters beyond those letters. Use those circle points!

It's a good idea, before it's time to enter the arena for competition, to find some sort of landmark to help you determine where the 10 meter point is. Look for an arena post or pylon, a clump of grass, a rock or a pile of manure -- anything that will help you judge where to touch the rail on each side of your circle.

For circles at A or C, you cross the centerline 20 meters from A or C (seems obvious, doesn't it?). If you know that the corner letters are 6 meters from the end of the ring, and that the next set of letters is another 12 meters down the long side, you can find an approximate crossing place for your circle. Find the S-R line for a circle at C (the V-L line for a circle at A) and aim to cross the centerline 2 meters beyond that line. Circle points for the win!

You'll use those same points to find where to cross the centerline for a 20 meter circle at E or B. You'll want to cross the centerline 10 meters on either side of X: the radius of your 20 meter circle is 10 meters. Remember that I and L are 12 meters from X. Aim for the centerline 2 meters to the inside of those letters for a great 20 meter circle.

Just to keep things interesting, occasionally a test will ask you to ride a 20 meter circle at R or S or V or P. Note that these are the same circles you would ride if you're asked to ride a 20 meter circle at X. See the diagram below for help.

20 meter circles at R, S, V, P

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Riding a 20 meter circle in the small arena is no different than riding one in the large arena -- the circle size is the same, only the landmarks change.

20 meter circles small arena

Circles at A and C (or X): In the small arena, just like the large, the corner letters (H, K, M, F) are six meters from the end of the arena. Therefore, your 20 meter circles at A and C touch the long sides of the arena 4 meters beyond the corner letters. However, in the small arena you cross the centerline exactly at X.

Usually it's pretty easy to find X in the small arena at competitions. Remember, everyone halts there -- look for the spot with the most hoofprints (and manure piles!).

Circles at B and E: When riding a circle which begins at B or E, your horse's shoulders should leave the track as they pass the letter. Remember to counteract those "rail magnets" by warning your horse ahead of time that you're planning to turn.

You'll cross the centerline 10 meters on either side of X. You can eyeball a spot halfway between X and A, and halfway between X and C, to find that spot. Or, look for that magic 4-meters-beyond-the-corner-letters spot, and cross the centerline opposite that. (The corner letters are 6 meters from the end of the ring. Add another 4 meters to find the ten meter mark. From that mark, it's another 10 meters to E or B.)

Again, it's a good idea to look for landmarks before you enter the competition arena.

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From the web: some super-cool outside resources (not part of -- and not my fault if they don't work!) that you are sure to find helpful.

How to ride the 20 meter circle.
From 40 Fundamentals of English Riding, from Riding Right Video

Dressage arena diagrams

Dressage arena "map"

Circle points

20 meter circles

15 meter circles

10 meter circles


Corners and half-circles

Okay, so just how accurate do I have to be?