A hillock, small heap, switch-back hill, old slag heap or industrial working.
A phrase which seems to have originated in the north of England and Scotland. Probably derived from tump, a barrow or Neolothic burial ground and numpsy meaning 'low life'
Generally, used in the plural, numpsy tumps.
Plenty of numpsy tumps where I go mountain biking.
The wretched moles have been busy again. Numpsy tumps everywhere.
I love the Scottish lochs and numpsy tumps.
Motoring at its best: the numpsy tumps of the Yorkshire wolds.