The horseshoe-shaped harbour is the front parlour of Hydra and the reason most people come. Stone quays curve around a deep, sheltered basin lined with cafes, fish tavernas, jewellery shops, and the offices of the hydrofoil companies. Cannons set into the seawall mark the entrance — there are two small stone bastions at either side, all that remains of the harbour defences from the Greek War of Independence.
Donkeys and mules wait at the central jetty to carry luggage up to the houses on the hill; this is the only transport on the island besides feet and boats. The harbour is at its best in the early morning, before the day-trippers arrive, and after the last evening hydrofoil leaves around 19:30 — the cafes empty out, the swallows come down low over the water, and the small fishing boats start unloading.