This is very similar to some of the European systems where riders and horses work their way up through levels in the theory that they learn to care for themselves as they undertake progressively more difficult rides. I believe that I've seen this in the British clubs. Pauline, do they have this in France? I think there may be something similar in Australia as well. It involves having a record book for each horse and seeing the progress as the rides are taken.
25 +Mile LD=Third Level (more conditioning and even more finesse)
50 Mile = Fourth Level (Now we are really testing you)
75 Mile= Prix St. George
Multi Day Rides = Intermediate I
100 Mile multi-day rides= Intermediate II
and last but not least- the Holy Grail
100 Miles? 1 Day=?Grand Prix
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I get the thing with the runners and the marathon, Bruce, I really do~ they are all still runners though.....just as training level dressage horses are still dressage horses, and TO ME 25 mile LD horses are still Endurance horses....they are just at a different level of TRAINING~? and YES some horses in dressage never progress past second level-? just like many Endurance horses never progress past 25 Miles.