http://infolara.com/naturism/beaches/beaches.shtml
Portugal
There are many Unofficial naturist beaches on the Algarve which are frequently used by naturists.
Plus you have the official beach at Isla de Tavira
Most of the beaches are to the west of Faro to wards Lagos and further.
Isla de Tavira. Which is an island? Is to the east and is best reached via the causeway and then tourist train
At Bavril. Unless you want to walk the 20 minutes or so to the beach and then turn left and walk for another 20mins.