Height and prominence are the most important metrics for the classifications of mountains by the UIAA; with isolation a distant third criterion.

[c] Note that topographical prominence is complex to measure and requires a survey of the entire contours of a peak, rather than a single point of height.

[8] These tables are therefore subject to being revised over time, and should not be amended or updated unless the entire DoBIH data is re-downloaded again.

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:[9][10]

suffixes: = twin As of 31 December 2023, 7,654 people had climbed all 282 Scottish Munros,[11] as of April 2020 eleven people had climbed all 1556 Marilyns of Great Britain,[h][12] while as of October 2022 only five people had climbed all the 2532 Simms of Great Britain,[i] Ken Whyte (Cruachan Beag 21/09/2010), Iain Thow (Cut Hill 07/06/2015), Michael Earnshaw (Cruach Fhiarach 16/07/2019), Rob Woodall (Sgurr Dhonuill West Top 28/06/2021) and Anne Bunn (Torr Ceum na Caillich, 24/09/2022).