South Mimms, sometimes spelt South Mymms, is a village and civil parish forming part of the Hertsmere district of Hertfordshire in the East of England. It is a small settlement located near to the junction of the M25 motorway with the A1(M) motorway and is perhaps more widely known because of the naming of the service station at that junction.
More information on the Wikipedia page [1]. The South Mimms Parish Council website is [2].