Start at the Halton Roundabout (A483/A5 Junction) and take the A5 into Wales to Capel Curig. In Capel Curig turn left onto the A4086 and follow to Beddgelert.
This route takes you from the English Welsh boarder up and into the Snowdonia National Park. Along the way you will pass along the River Dee, the Afon Llugwy, green pastures, through Welsh villages and into green and rocky mountains
This road has plenty of sweeping curves and change in elevation. The roads are in great shape but beware while in the National Park if it is raining as the roads could be covered in running water in places.
Betws-y-Coed is a good half way point to stop. It is a nice Welsh village with good shops and restaurants. You will also come accross Rhaeadr Ewynnol Swallow Falls Waterfall. If you want to camp and hike, stop at Llyn Gwynant Campsite where can enjoy the lake or head over to hike to the top of Snowdon Peak.