On my last year’s summer vacation I found some very idyllic beaches on Costa Dorada (Tarragona).
1) Playa del Torn (Catalunya’s first naturist beach)
Playa del Torn is a long golden sandy nudist beach that joins the sea with a hilly natural park. The beach is relatively isolated and can only be reached through the forest. There are no buildings nearby. There is an awesome chiringuito (beach bar) on the beach though were you can chill and have a drink. The only thing that’s a little freaky about the place is the fact that there is a nuclear plant not far from it. The beach is surrounded by forest, therefore, the plant is not visible from the beach but you might see it on your way there. Nevertheless, thanks to the nuclear plant, there are no other constructions in the vicinity of the natural park. Further, the beach is very clean and well maintained.
2) Les tres cales (the three coves)
Les Tres Cales is a small village between L’Ametlla de Mar and L’Hospitalet de l’Infant (about 15 minutes from Playa del Torn). And as its name suggests, the village has several beautiful coves with golden sandy beaches. The coves can be easily reached by foot and they are next to each other. There are walking paths that connect the them. Within about 30 minutes you can walk from Cala Mosques passing through Cala Forn (the one you can see on the picture) and Cala Vidre till Cala de Sant Jordi and explore the Sant Jordi Castell on the way.
The best place to stay around there is at one of the quiet camping sites which are great for travelers on a low budget but which are still very comfortable.