Vaghia waters are said to be the coldest on the island. It is a pebble beach with tamarisks for shade and often quieter than most easily accessible beaches.
It is 7 kilometers from Skala and only 1km from the bus station on Kambos beach, from there it takes about 15 minutes on foot.
To get there you turn right at the junction at the end of Kambos beach, you go straight up the hill and then back down where the beach awaits you.
There is a café on your way down so grab some water and whatever else you need, it will save you the walk up the steep hill later.