The island of Samothraki is located in the north-eastern Aegean Sea (Thraki, Greece). At only 178 km2 Samothraki is a high mountain massif that dominates the northern Aegean Sea and packs a lot into its small size. The island is bursting with picture perfect views of pristine cultural landscapes, an impressive geology and varied natural vegetation including ancient oriental plane forests, mountain wilderness, abundant fresh waters in the form springs and perennial streams with waterfalls which plunge into deep glassy rock pools, hot springs, small coastal wetlands, rocky beaches and a crystal clear seas. Samothraki is a perfect destination for naturalists, thrill-seeking adventurers and dedicated scientists; it seems to attract people who really care for its natural wonders. With a small local population of under 3,000 (2011 census) and a low population density (15 persons/km2), its main economic activities are agriculture, livestock breeding and small scale tourism. The island is relatively undisturbed by the modern world and remains one of the last virgin islands of Greece. It is thus self-evident that a large portion of this unique island with its rich biodiversity and deep history is part of the NATURA 2000 Network and is a UNESCO Biosphere Reserve candidate. Hydrologic and geochemical monitoring has been conducted while water and biological quality data of surface have been collected since 2000. SNO is managed by the Institute of Marine Biological Resources and Inland Waters (IMBRIW, http://imbriw.hcmr.gr/en/) of the Hellenic Centre for Marine Research (HCMR, http://www.hcmr.gr/en/).