Tróia is a peninsula located in Grândola Municipality (parish of Carvalhal [pt]), Portugal, next to the Sado River estuary. Tourism is the peninsula's main activity due to its long beaches facing the Atlantic. There is a ferry boat connection between the peninsula and the city of Setubal. Tróia has important archaeological sites dating from the time when the peninsula was an island called Acalá, settled by the Romans.

The peninsula has a casino, many hotels, some restaurants, a swimming pool and white sand beaches facing the Atlantic Ocean. Here visitors can also find Roman ruins and the Porto Palafítico da carrasqueira.

The beaches nearest to Setubal are busy during summer months, especially at weekends. Stilted walkways link these beaches to the harbour and marina areas, protecting the vulnerable dune flora. There are small cafes on the beaches and larger ones around the marina near the foot-passenger ferry.

There are beaches both facing the Atlantic (west) as well as the Sado River (east).