No special access issues
🅿️ at the big parking of Buthiers for most part of the area. For the part closer to trojan war one could also park at the tarmac parking before the other one. Which ever parking you chose, the approach by walking will not be more than 1..2 minutes.
From the big parking in middle of Buthiers tennis and Piscine, literally you could throw a stone to the first boulder. Approach to this one will be around 30s.