A4066 (Hirwaun - Brecon Beacons)
|To:||Beacons Reservoir (SN988183)|
|Length:||9.5 miles (15.3 km)|
|Met:||A465, A4059, A470|
|Now part of:||A4059|
|Route outline (key)|
The original allocation of the A4066 number was to what is now the northern section of A4059.
The road started at a crossroads in the centre of Hirwaun and headed north out of town along Penderyn Road, soon going through Penderyn itself. The road then continued northwards, climbing into the Brecon Beacons to end on the A470 by the Beacons Reservoir, about a mile south of that road's summit.
The A4066 was renumbered to become a northern extension of the A4059 in the 1935 Road numbering revision. That road now bypasses Hirwaun (although the bypass is newer than that of the A465) and so the old road in Hirwaun is now a dead end.