The closest beach to Mykonos Town, about 1 km south of the harbour on the road toward Ornos. Megali Ammos (meaning "big sand") is a narrow strip of organised beach popular with those staying in town who want a quick swim without catching a bus. The water is clean and the beach is sheltered. A couple of beach bars operate here in season.
It is not the most beautiful beach on the island and the proximity to the port road means some noise, but the convenience factor is real. If you are based in Chora and want a morning swim before the beach clubs at the south coast get going, this is the practical choice.