The hot springs at the northern tip of the island, a ten-minute walk from the ferry port, are one of the more surreal bathing experiences in the Mediterranean. Geothermal vents heat the shallow water to around 35–40°C in the main pool, and the sea beside it bubbles with underwater fumaroles. The water is yellow-tinged with sulphur, the smell is unmistakable, and the combination makes visitors look like they're being slow-cooked in a volcanic stew.
Go early — by 11am the day-trippers from Lipari arrive in numbers and the pools become crowded. Your swimsuit will be permanently discoloured by the sulphur; bring one you're happy to sacrifice. The thermal mud from the pools is traditionally applied as a face mask and left to dry before entering the water — entirely optional, but joining in is part of the experience. Rinse thoroughly afterward and wash your swimsuit immediately.