This climb is named after 2500 year old fort that is preserved above the climb’s finish (see more below).
The climb is on an extremely narrow (max one lane) road that were are on 2.3 kilometers at a healthy 10% average grade.
Extremely narrow road
The climb starts at a T intersection next to a white cottage.
We are surrounded by thick hedge bordering both sides of the road until the fork in the road at 650 meters (go right here).
As we exit the hedgerows the views open up to pasture land and grazing sheep. The climb ends at a cattleguard and the fort is uphill to your left from that point.
End of the line.
Eventually you exit the thick vegetation and you can see down to the farm land below. The climb finishes right at a cattle guard.
It’s worth mentioning the danger going down this. The road is so narrow that any car will take up 95% of available space. I had to slam on the brakes and climb off my bike to let a car pass at one point. Going down the hill any faster than 15mph is nearly suicidal.
Steepest kilometer begins at 300 m (10.4%)
Moel Arthur (Bryngaer) Hill Fort:
“Built over 2,500 years ago around 500 BC, Moel Arthur is one of a series of Iron Age hill forts to be found on the summits of the hills of the beautiful Clwydian Range in North Wales. Overlooking the Vale of Clwyd, it sits between Moel Llys y Coed and another hillfort at Penycloddiau.
Although relatively small at just over 2 hectares in size, the fort boasts some of the largest earthworks, banks and ditches in the area. These are most impressive on the gently sloping northern side of the fort where there is a double rampart.
Evidence has been found showing activity on Moel Arthur not only during the Iron Age but also earlier in the Bronze Age. A possible Bronze Age burial mound lies in the centre of the fort and in 1962, three copper Bronze Age flat axes were found within the ramparts. Earlier excavations also turned up coarse Roman pottery and flint arrowheads, suggesting the hill fort was in use both before and after the Iron Age.” Historic-uk.com
“Moel Arthur is a historic Iron Age fort built in the Vale Of Clwyd. The fort was chosen for its defensive properties – situated on a steep hill, affording great views around the surrounding countryside. These defensive properties also help to make Moel Arthur an excellent road climb for cyclists, although the climb doesn’t go to the top of unique hill, you still have a hard climb up towards the peak.
Starting from the small village of Y Groes Fawr, the climb is short and steep, and packs in an impressive 219m of height gain over 1.4 miles. , It’s unrelenting gradient makes it a real test. With a KOM time of 8.05, it is not a short, sharp shock you can just power over, you need a good pacing to keep going all the way to the top.
The climb is steepest at over 0.5 miles, where it reaches 20%, after this real difficult section, it eases off a little for the last half a mile, but the climb averages a good 10% for the one and half miles of the climb.” More
This climb begins just east of Llandyrnog, Wales (pop. 1,096, 2011)