The entrance to Alec's Field is directly opposite the Antelope Pub in Hazelbury Bryan. For 'SatNav' users DT10 2EB should get you there, but for the rest of us ....
Hazelbury Bryan is about 5 miles South West of Sturminster Newton, 12 miles West of Blandford and about 15 miles North of Dorchester.
On the map below, Alec's Field is shown as the green shaded area at the junction of Partway Lane, The Causeway and Water Knap.
On the day, there will be marshalls outside the gate and traffic cones, so, if you're driving a classic vehicle of any sort, there's very little chance of getting past without being diverted onto the field!!