Race around some land (4)
'some land' is the definition.
(I've seen this before)
'race around' is the wordplay.
'around' is an anagram indicator.
'race' is an anagram of 'ACRE'.
(Other definitions for acre that I've seen before include "Care about the piece of land", "Unit of area of 4,840 square yards", "amount of land", "Site of battle", "Muslims here besieged".)