Archive of Transactions
Excavations at Grim’s Dyke, Harrow, 1979
Robert Ellis
Excavations were carried out in the grounds of the Grim’s Dyke Hotel (TQ 14169288), in advance of a redevelopment which included levelling part of Grim’s Dyke, a Scheduled Ancient Monument.
Grim’s Dyke runs continuously for about 3km across Harrow Weald Common, Middlesex, and at this point stands some 15m wide and 2m high, with a ditch 4m wide and 1m deep on the south side. Although a 5th or 6th-century AD date has generally been favoured – and it has been suggested that the earthwork is an extension of the post-Roman earthwork in Pear Wood some 3km east of the present site – at no point had previous excavation produced clear dating evidence. Here, a section was cut across the bank and a radiocarbon date of ad 50 +/- 80 was obtained from a charcoal sample stratified within it. Although far from conclusive, this hints that Grim’s Dyke may in fact be late Iron Age, considerably earlier than the Pear Wood earthwork.
[Transactions 33(1982), pp 173 – 6; abstract by Francis Grew, 09-Dec-1997]