Best place to park is in the village of Upper Rissington and start from there.
The road is marked as "Unsuitable for Motors" so there is hardly any traffic along this road/track. It's a lovely short walk with open views on one side. You may bump into dog walkers along the lane or farm traffic.
During the weekend you may see gliders taking off/landing at RAF Little Rissington and I have seen red kite, buzzards and owls in the area.