(27) The Harpstone (SY 98 SW; 92168058; Plate 217), monolith, of limestone, stands 1,180 yds. E.S.E. of St. Michael’s Church, on the bank of a small stream and just inside the W. edge of Hurpston Coppice on ground falling gently N. to the Corfe River in the marshy valley bottom. It is 7¼ ft. high with a jagged and uneven top and has a maximum width of 3¾ ft. E.-W. and 3 ft. N.-S. The four faces are largely disfigured by vertical grooves and hollows, the result of weathering. Its origin is unknown. The place-name Herpston (1340) may refer to the stone, which stands on the bank between Herpston and Hyde manors and flanks the ancient road from Creech to Kimmeridge. (Hutchins I, 609; Fägersten, 136.)
‘Stones’, in An Inventory of the Historical Monuments in Dorset, Volume 2, South east (London, 1970), pp. 512-515. British History Online british-history.ac.uk/rchme/dorset/vol2/pp512-515