From A1 take first exit at Stirling Corner (by Superstores). At next roundabout go straight ahead into Furzehill Road. At end of road turn right. At big roundabout by McDonalds take first exit into Brook Road. Use car park on right (note this is pay and display).
Borehamwood & Elstree station (roughly 40 minutes from St. Pancras) is approx 10 minutes walk from ground. Walk through town centre, past McDonalds and turn left into Brook Road. Ground visible on right.