In the morning, I took the bus from Betws-y-Coed to Caernarfon on the coast to look at the spectacular, huge castle next to the harbor. To get there I had to change buses in Llanberis which is famous for its massive slate quarries which can be seen in the mountains above the village. The bus went up to the trailhead to Snowdon Mountain and there was amazing mountain scenery all along the way.
The village of Caernarfon was charming and scenic with a harbour full of boats. There was a nice long walkway over the bridge and along the ocean. Caernarfon would be a good place to spend the night and see the castle lit up at night.