This is a little Multi in Dacre Park.
At the start coordinates you'll find a sign with circles on it:
A = Eighth digit in the phone number
B = First digit in the Bylaw#
C = Seventh digit in phone number
D = Blue circles
E = Green circles
F = Letters in first word minus 1
Checksum: 21
You will find the final at: N49 1(A+B).ABC W122 4F.DEF
Enjoy and please, be careful when climbing!