|Length:||4.8 miles (7.7 km)|
|Meets:||A486, B4624, B4459, A485|
|Route outline (key)|
The B4336 is a rural B-road in northern Carmarthenshire.
It runs from the A486 Llandysul bypass eastwards through Llanfihangel-ar-arth to Llanlliwni on the A485. Although Llandysul itself is in Cardiganshire the B4336 remains in Carmarthenshire for its entire route.
Before construction of the Llandysul bypass (opened in 2009), the B4336 began at a junction with the pre-bypass route of the A486 immediately south of the old Teifi bridge. Now the first 450 m of the original route have been subsumed into the B4624, and the B4436 has instead been rerouted along a newly built section of road leading to a roundabout on the bypass.
Heading east, our route follows the north bank of River Tyweli for 1.7 km before diverging to the left at Penlan to climb a gentle hill and then descend into Llanfihangel-an-arth, where it crosses the B4459. Another climb, with good views across the valley of the Teifi to the left, brings the road to its terminus at the south end of the spread-out village of Llanllwni on the A485.