However, the earliest reference to Tollcross dates from 1439. The names "tolcors", "towcroce", "tolcroce" appear on 16th century maps, taking the form "towcorse" as late as 1787. It has been suggested that "cros" is a later form of "cors" (as in Old Welsh "toll cors", meaning a "boggy hollow") and that the ending "-corse" would have aptly described the low-lying area beside the now culverted Lochrin Burn running between the slopes of the Burgh Muir and the High Riggs south of the Grassmarket. Etymologically however this makes no sense, as the historic maps show the original settlement confined to the high ground at High Riggs. The closest "boggy hollow" was 1km to the north, just west of the Nor' Loch.