[2][3] The first list was compiled in the 1920s by John Rooke Corbett, a Bristol-based climber and Scottish Mountaineering Club ("SMC") member, and was published posthumously, after his sister passed it to the SMC, in the 1953 edition of Munro's Tables.

[2][4] Corbetts are the next category down from the Munros and Munro Tops in terms of height (i.e. below the elevation threshold of 3,000 ft or 914.4 m), but their explicit prominence threshold of 500 feet (152 m), ensure they are material peaks.

[6] 21 of these 222 Corbetts have a prominence that exceeds the P600 threshold of 600 metres (1,969 ft), which would class them as "Majors".

[6] The highest Corbett, Beinn a' Chlaidheimh, at 914 metres (2,999 ft) is just below the threshold for a Munro, a status it held until it was demoted in 2012 based on new surveys;[7] it ranks as the 478th highest mountain in the British Isles, on the Simms classification.

The DoBIH uses the following codes for the various classifications of mountains and hills in the British Isles, which many of the above peaks also fall into:[13][14]