They are all heavily touristed and expensive. Skopelos is less commercialised than Skiathos, but is following hot on its trail. There are some lovely sheltered beaches, but they are often pebbled rather than sandy. Alonnisos is still a serene island, partly because the rocky terrain makes building an airport runway impossible. The water around Alonnisos has been declared a marine park and consequently is the cleanest in the Aegean.
Every house has a cesspit, so no waste goes into the sea.
Skyros is less developed than the other three, designed to attract posers rather than package tourists. The five Saronic Gulf islands are the closest of all to Athens, and Salamis is virtually a suburb of the capital. Aegina , Hydra , Spetses and Poros are all surprisingly varied in architecture and terrain, but they all receive an inordinate number of tourists and are expensive. Hydra, once the rendezvous of artists, writers and beautiful people, is now overrun with holiday-makers but manages to retain an air of superiority and grandeur. There are 46 villages in the region of Zagoria, north of Ioannina.