Glen led a tour (4)
I believe the answer is:
dale
'glen' is the definition.
(I've seen this in another clue)
'led a tour' is the wordplay.
'tour' indicates anagramming the letters (I've seen 'tours' mean this (the letters roam or tour around)).
'led'+'a'='leda'
'leda' with letters rearranged gives 'DALE'.
(Other definitions for dale that I've seen before include "See 8" , "Valley; Trollope's Bell and Lily" , "Valley; old radio soap family" , "Lead out of the river valley" , "Up hill and down . . . ." .)