What Is Alonissos Known For?

Alonissos holds the largest protected marine area anywhere in Europe, and it stands as the last real stronghold for one of the rarest marine mammals on the planet.

Alonissos is known first for the National Marine Park of Alonissos and Northern Sporades, established in 1992 by Presidential Decree as the first marine park in Greece. Covering roughly 2,200 square kilometers of the Aegean, it includes Alonissos itself, the only inhabited island in the group, alongside six smaller islands: Peristera, Kyra Panagia, Gioura, Psathoura, Piperi, and Skantzoura, with Piperi serving as the park's strictly protected core zone.

The park exists primarily to protect the Mediterranean monk seal, considered the rarest pinniped species in the world. Ancient Greeks associated the animal with Poseidon and Apollo and depicted it on vases throughout antiquity, though Roman hunters later drove the population toward collapse for its fur and oil. By the early 1990s, fewer than 600 monk seals remained globally, and the species was classified as critically endangered. Conservation efforts tied directly to the Alonissos park have since helped the population recover to a status of vulnerable by 2022, and monitoring in 2026 recorded 21 newborn pups, the highest annual count in nearly 40 years of tracking, born mostly around Piperi and southeastern Skopelos.

Beyond the seals, the park protects the Underwater Archaeological Park of Peristera, home to one of the most significant ancient shipwrecks discovered in Greek waters, along with dolphins, loggerhead turtles, and more than 300 recorded fish species throughout its waters.

Alonissos suits travelers wanting real conservation work alongside genuine natural beauty, connecting by ferry to Skopelos and Skiathos for anyone extending a trip through the Sporades.