Only a small walk, good for an evening, but nevertheless enjoyable. The distance from one end (from Housesteads Road, Sandsfield Park) to the other (Mardale Road, Raffles) is 1.25 miles, maybe slightly more. Therefore a circular walk will be 2.5 miles so if you walk from your house or from town and back will obviously give you a couple more miles.
Housesteads Road can be reached from the bypass roundabout at Moorhouse Road, turning left into Sandsfield Road, next left is Housesteads Road, the gate can be found approx after 50 m on the left (don't quote me if I am wrong, I am useless with directions! Haha!). Or you can get to Sandsfield Road coming from Orton Road, Morton West.
When walking from town, Mardale Road is off Newton Road, turning left at the Post Office, then right, next one left. The park starts on the right hand side.