Well-signposted from the northern end of the main strip, the Phanoy Cave is a cool relief on a hot day. The cave lies about halfway up a steep track that leads to a striking viewpoint over the Nam Ou and Muang Ngoi Neua below. Definitely take a torch (flashlight) for the cave as a cluster of Buddha relics lies about a 10-minute walk through a pitch-black passageway.
It's best to allow about one to two hours to see both the cave and the viewpoint. Bring water from town as there is none available at the cave or viewpoint.