Hi Pablo
Arrieta is a small village in the north of the island. It has a really nice beach called La Garita and there are a couple of bar / restaurants on the beach. The village has a petrol station, a bakery, a huge sociedad and several really good restaurants which specialise in fish. It's in the municipality of Haria, which is the least populous on the island. Whilst there visit any (or all) of the following: Jardin de Cactus, Jameos Del Agua, Cuevas de los verdes, Mirador del Rio, and the town of Haria (great Saturday market).
BTW, there is another Arrieta in Biscay Province, Northern Spain.
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