Is Praia da Rocha part of Portimao?
Yes, Praia da Rocha is part of the municipality of Portimão. It is located on the southern end of the city. Although it is officially within Portimão, Praia da Rocha operates largely as an independent resort area. While it has a year-round local population, the area becomes significantly busier during the peak season from April to October and is much quieter otherwise.
You can read about each area in their independent city guides:
