Three uninhabited islands forming the mouth of the Ría de Vigo, the Islas Cíes are one of the great natural treasures of Spain. Access is by seasonal ferry from Vigo's passenger terminal — the journey takes about 45 minutes. Once there, the options are simple: swim, walk the trails through pine and eucalyptus forest, snorkel in the clear water, or eat at the single campsite-restaurant on the island.
Rodas beach, a 1 km arc of bright sand linking two of the islands, is the showpiece. The water is shallow, calm, and turquoise — extraordinary for the Atlantic coast. Birdwatchers come for the large yellow-legged gull colony (one of Europe's biggest) and the chance of seeing shags and blue rock thrushes. Camping is possible with a reservation; no overnight accommodation otherwise, and all day visitors must leave on the last ferry. The islands are only accessible April to October.