Going to the Cies Islands is like traveling to the Caribbean with icy water. It is only twenty minutes by boat from Vigo. You can also get there from Bayonne. I enjoy visiting the area, walking the paths and swimming in the icy water of the Rhodes beach. It is unfortunate that the British newspaper The Guardian proclaimed this beach as the best beach as this has lead to an increase in visitors. It is losing its wild and rugged spirit as a result. I recommend going to The South Island, or San Martin, instead. It has a smaller beach than that of Rhodes but also very beautiful. This island is however only accessible by private boat. You have to pay and need permission. This means that even in the month of August the island is very quiet and uncrowded.
The Piscinas de la Virgen are the most popular natural pools in the city. The sulfuric water is fed by an underground volcanic spring and and clean, flowing waterfall, and has natural curative powers so it's popular among both locals and tourists.