set any measure of topographic prominence by which a peak qualified as a separate mountain, so there has been much debate about how distinct two hills must be if they are to be counted as two separate Munros. The Scottish Mountaineering Club has revised the tables, both in response to new height data on Ordnance Survey maps and to address the perceived inconsistency as to which peaks qualify for Munro status. In 1992, the publication of Alan Dawson's book Relative Hills of Britain, showed that three Munro Tops not already considered summits, had a prominence of more than . Given this they would have qualified as Corbett summits had they been under 3,000 feet. In the 1997 tables these three Munro Tops, on Beinn Alligin, Beinn Eighe and Buachaille Etive Beag, gained full Munro summit status. Dawson's book also highlighted a number of significant Munro Tops with as much as of prominence which were not listed as Munro Tops. The 1997 tables promoted five of these to full Munro status. A total of 197 Munros have a topographic prominence of over and are regarded by Peakbaggers as Real Munros. 130 Scottish mountains over 1000m, with a topographic prominence of over have been termed Metric Munros. Other classification schemes in Scotland, such as the Corbetts and Grahams , require a peak to have a prominence of at least for inclusion. The Munros, however, lack a rigid set of criteria for inclusion, with many summits of lesser prominence listed, principally because their summits are hard to reach. During May and July 2009 the Munro Society re-surveyed several mountains that are known to be close to the 3,000 ft figure to determine their height more accurately. On 10 September 2009 the society announced that the mountain Sgùrr nan Ceannaichean, south of Glen Carron, had a height of . Therefore, the Scottish Mountaineering Club removed the Munro status of Sgùrr nan Ceannaichean and this mountain is now a Corbett. In a Summer 2011 height survey by The Munro Society, Beinn a' Chlaidheimh was found to be and thus short of the Munro mark. On 6 September 2012, the Scottish Mountaineering Club demoted it from Munro to Corbett status. On 26 August 2020, the SMC confirmed that Beinn a' Chroin West Top at 938m was deleted as a Munro Top and Beinn a' Chroin East Top became the new Munro Top at 940.1m. The summit