Cross Country runners will remember this location from Cuppers.
4 miles (each way) - Down Hills Road past Addenbrooke's Hospital, keep going straight, past the Golf Course and up the Hill (mind the beautiful view on your way back.)
Start at the public car park on the other side of the hill.
The Forest is nice and away from any traffic. Go to the east end and be disgusted about the extension of the Gog Magog Golf course - the first time I saw it, it was a moon surface!
I am not going to suggest a route through the park. Go and take a look at the map at the car park and explore it yourself. Mind the prehistoric ring fort.
On its own not suited for very long runs unless you go down to the Roman Road at the East side of the park.
The author cannot be held responsible for any kind of injuries, trespassing violations, or anything else occurring in connection with following the stated routes. Anyone may do so only on their own risk.