From Roader's Digest: The SABRE Wiki
|Length:||9.2 miles (14.8 km)|
|Meets:||A497, A499, A497|
|Route outline (key)|
The B4354 is exceptionally straight for a Class II road. You might be forgiven for thinking that it could be Roman in origin, but the truth is stranger. In the early 1800s, there was a competition to choose a new London-to-Dublin mail route. Holyhead, Llandudno and New Quay were all in the running, as was Porth Dinllaen near Morfa Nefyn (offering a shorter sea crossing than Holyhead could). As part of the bid, this road and what is now the B4412 were built.
It is curious that its number doesn't fit in with the rest of the B-roads in the area, which have B44xx designations. The reason for this is that the road was originally unclassified, not gaining its number until around 1930; presumably this road was not seen as important in 1922.
We start 2.5 km west of Llanystumdwy at a junction on the A497 shyly signposted just "B4354" (with no listed destinations on the flag). You get the impression that the authorities don't really want us to use the road. Actually, they'd far prefer traffic to use the roundabout junction 1.5 km further on, which serves the unclassified road running south out of Chwilog (which we'll get to in a minute).
The B4354 turns a sharp left after the junction, and you can see the older route of the road (before junction improvements) coming in from the right. The road continues straight for about a mile (with a kink to the right about half way) until it reaches the outskirts of Chwilog village. The speed limit drops from NSL to 30 mph, and a little after that the road narrows and we lose priority in favour of oncoming traffic. Next comes a T-junction where the unclassified road to the A497 mentioned earlier is the left turn, and the continuing B4354 is a TOTSO to the right.
The route climbs up through Chwilog village in a straight line, passing a bus turning circle on the right. Although the speed limit is 30 mph, there is traffic calming in the form of regular speed cushions.
Leaving Chwilog, the speed limit resumes as NSL, and we continue in a straight line for a mile and a half, except for a kink to our left after just over half a mile. We're now approaching Y Ffôr, formerly (and still referred to by some Welsh-speaking locals as) Four Crosses. To our left we have the factory buildings of South Caernarfon Creameries. The speed limit drops to 40 mph, as we negotiate a bridge over the Afon Erch and climb into Y Ffôr itself, where the speed limit drops to 30 mph.
We now meet the A499 at a slightly staggered crossroads, with stop signs for the B4354 in both directions. The speed limit returns to NSL but the road quality is now lower, with not enough width to need a central line. A few bends take the road onto another dead-straight section, which goes through a wood and passes a holiday park before the central line comes back.
The road starts winding again as it descends to cross the Afon Rhyd-hir, scarcely a stream at this point, then becomes straight again on the far side of the valley. We approach - and pass to the south of - some wooded hills, skirting the edge of Garn Boduan; the road is also wooded here. It's not long before the end of the road is reached, at a T-junction back on the A487. That road detoured to the south via Pwllheli adding only a short distance to its length.