Ghioura (from Greek Γιούρα) is part of the Sporades, specifically the archipelago of islets of Alonissos. It is located northeast of Alonissos (16 nautical miles), after Kyra Panagia (2 nautical miles), and is a wild and very mountainous island: practically impregnable.
It has an area of 11 km² and is deserted, except for a few forest guards.
Its highest peak reaches 570 meters. One side of the island has some Mediterranean scrub, while the other is completely barren and scattered with landslides, sea caves, and cliffs.
Since 1988, Ghioura, along with the other islets of the archipelago, has been declared a marine park to preserve the environment, still frequented by the rare monk seal. Around the island, swimming, snorkeling, photography, and filming are allowed, but neither fishing nor hunting is permitted.
Many seabirds, some rare, and a rare species of wild goat, the cri-cri goat, similar to those found in Crete, live on the island.
The island has no anchorages, and the most convenient landing spot is along the southwestern coast. The sea around the island is incredibly clear: the most transparent in the archipelago.