Vai may be the most popular beach in the area but if you come so far, you have to go to Erimoupoli. It has a beautiful, virgin beach with fine sand and blue green waters, two small gulfs (to one of which you can rest under the shadow of palm trees) and the archaeological site of Itanos. A diving mask is the absolutely necessary thing to carry with you, to explore the underwater ancient civilization. Erimoupoli is not well organized (luckily), but has become known to the locals as well.