A Tump is a hill of any height in Britain or the Isle of Man that has a drop of at least 30 metres on all sides. There were 16847 Tumps at the end of 2015.
The complete list of Tumps is still being refined. It is a co-operative effort involving several people, now largely co-ordinated by the editorial team of the Database of British and Irish Hills. The overall list was assembled by Mark Jackson. As well as doing substantial original research, Mark incorporated the work of several people including Alan Dawson (hills over 600m), Michael Dewey, David Purchase and Rob Woodall (hills from 500-609m), Clem Clements (hills from 300-500m) and Myrddyn Phillips (hills from 400-500m in England and from 30m to 500m in Wales). More information about Tumps is available in these sources:
No-one has climbed all the Tumps and no-one is likely to, as many Tumps are sea stacks that have never been climbed. However, several people have climbed over 4000 Tumps, and Rob Woodall had climbed over 9600 of them by the end of 2015.