…long walk to reach Eastern Kinross, initially (4)
I believe the answer is:
trek
'long walk' is the definition.
(I've seen this before)
'to reach eastern kinross initially' is the wordplay.
'initially' suggests taking the first letters.
The initial letters of 'to reach eastern kinross' is 'TREK'.
(Other definitions for trek that I've seen before include "Long and difficult trip" , "A long arduous walk" , "Great journey" , "Long and difficult journey" , "Long walk, expedition" .)