I have just added this to the map of places to fly your drone at Drone Scene:
Land owner permission not required.
There a little car park if you follow the road from Ivanhoe around the actual beacon towards Ashridge Estate. As soon as you tucking the hill, the car park is there.
Just walk following the road down until you find a hill. The beacon is at the top. If it is a very nice day might be busy, so try to avoid those days.
The originator declared that this location was not inside a Flight Restriction Zone at the time of being flown on 30/01/2019. It remains the responsibility of any pilot to check for any changes before flying at the same location.