Hinitsa is the name of two nice sandy beaches (separated with a tiny peninsula), located opposite the so named islet, in a charming bay next to Porto Heli bay.
The first bay actually belongs to a large hotel (but is public) and has umbrellas and grass in the shore. The second bay is far more picturesque, with sand and pine trees, but often crowded. The colour of the sea is impressive with emerald-green shades, however we have doubts about its cleaniness, because of the hotels around and the many yachts that usually anchor there.
In any case though, the setting is beautiful and attracts many yachters (and non-yachters) who prefer to swim close to Porto Heli and Spetses. The area is a quite popular anchorage.
The well known taverna on the second beach, is very good and convinient and attracts many people from the area.