...hurdling could also have been used.
Yes, one of the interesting things about the Avenues leading into Avebury is their width - they really are wide for a purely (human) ceremonial route. The sphinx-lined avenues leading to Karnack Temple, for example, are quite narrow by comparison. The same generous width of the Avebury Avenues also applies to the Chelmer (Springfield) Cursus that once led down from a wooden circle at one end of the cursus to the river at the other. I can't help thinking that the Chelmer Cursus might have been a clearly defined, and as far as livestock are concerned a safe and easy route to follow, from one end of the cursus to the Chelmer River and water meadows at the other (where incidentally cattle still graze today).