Waterfall — Northeast coast
Fonias ("murderer" in Greek — the name comes from local legend, not anything that happens on the hike) is the island's largest stream, and the hike alongside it is the single most popular activity on Samothraki after the Sanctuary.
The lower pools, a short and easy walk from the road, are the ones most visitors reach — clear, cold, and framed by smooth rock. Further upstream the terrain gets steeper, leading eventually to Kleidosi, the island's highest waterfall at 35 metres, for those who want to make a full day of it.
Come prepared to swim — the pools are the whole point — and expect the water to be genuinely cold even in the height of summer, fed by Mount Saos above.