If you were a military archer in the middle ages and needed to attack an enemy the other side of trees, walls, battlements, houses and such 'hidden' targets how would you achieve this? The answer is you would shoot into the air with the aim of showering arrows down on your enemies.
This is the style of shooting required for roving marks. A mark is a target and roving means moving around/mobile not just shooting from one place. Targets may range in distance from 5 to 250 yards, with no known distances.
Arrows must be shot into the air and not directly at targets, for instance one might shoot 200 yards high to achieve a mere 60 yards of forward distance.
In the middle ages this style of practice combat archery was used to hone archers skills in terms of judging distances, shooting together, encouraging team spirit, toning muscles and hitting targets hard and fast.
The number of arrows shot at each mark varies from 1 to 6 depending on the 'whim' of the 'Captain to the Marks'. Marks may be prechosen and the field laid out, or the archer nearest the mark choses the next one etc etc.