Galissas is a resort on the west coast of Syros and has the longest beach on the island (note that all beaches of Syros are small and this one is not endless, it is about 300 meters long). Galissas beach is Blue Flag awarded, with fine soft sand and shallow water. It is set in a cove between high cliffs and the water is usually calm. Sunbeds and parasols to rent are available on part of the beach, as well as natural shade cast by the tamarix trees.
There are some nice taverns by the sea, mini markets, many small family hotels and one big hotel complex. From Galissas (and from Kini) you can enjoy the sunset.