
Die griechische Insel Hydra oder Ydra (griechisch Ύδρα (f. sg)) gehört zur Gruppe der Saronischen Inseln und liegt etwa 65 km südwestlich von Athen. Gleichzeitig bildet sie eine Gemeinde (dímos, δήμος) im attischen Regionalbezirk Inseln, der auch die 2,2 km nordwestlich gelegene Nachbarinsel Dokos angehört, sowie auch Agios Georgios, die 31 km nordöstlich von Hydra liegt. Sie wird mehrfach täglich von der Hafenstadt Piräus aus angefahren; auch zu den Nachbarinseln bestehen zumindest in der Hauptsaison regelmäßige Fährverbindungen.
Hydra gelangte zu ihrem Namen, als sie noch eine sehr wasserreiche und fruchtbare Insel war. Heutzutage kommt jeden Tag ein Schiff, das Trinkwasser liefert.
Hydra (Greek: Ύδρα, pronounced [ˈiðra] in modern Greek) is one of the Saronic Islands of Greece, located in the Aegean Sea between the Saronic Gulf and the Argolic Gulf. It is separated from the Peloponnese by narrow strip of water. In ancient times, the island was known as Hydrea (Υδρέα, derived from the Greek word for "water"), which was a reference to the springs on the island.
The municipality Hydra consists of the islands Hydra (area 52 km2), Dokos (pop. 18, area 13.5 km2) and a few uninhabited islets. The province of Hydra (Greek: Επαρχία Ύδρας) was one of the provinces of the Piraeus Prefecture. Its territory corresponded with that of the current municipality.[2] It was abolished in 2006.
There is one main town, known simply as "Hydra port" (pop. 1,900 in 2011). It consists of a crescent-shaped harbor, around which is centered a strand of restaurants, shops, markets, and galleries that cater to tourists and locals (Hydriots). Steep stone streets lead up and outwards from the harbor area. Most of the local residences, as well as the hostelries on the island are located on these streets. Other small villages or hamlets on the island include Mandraki (pop. 11), Kamini, Vlychos (19), Palamidas, Episkopi, and Molos.