Lisboa is the only European Capital city located so close to sandy beaches, and although the waters are not as warm as in the Algarve, the Lisboa coast offers beautiful beaches from sheltered little coves to miles of dune-backed sands. Most of them are clean and fly the European Union Blue Flag for excellence and the locals Lisbon usually head to the beach every chance they get, on holidays, weekends, or even for an hour or two after work, including in the winter months.

Adraga beach - Sintra, photo by Junta do Turismo da Costa do Estoril
Along the railway line linking Lisbon to Cascais are several broad beaches that are usually packed in summer, and Carcavelos which is particularly popular with youngsters who play beach soccer there. Tamariz in Estoril is another good option and as well as Guincho, a beautiful beach known world-wide for surfing. All these beaches are within 20 to 30 minutes from the capital.
For the longest stretches of sand, head south of the city, to Costa da Caparica, or better yet, to refreshing Meco, sandy Troia, or secluded Adraga, ranked as one of the best beaches in Europe. Portinho da Arrábida is another favourite and is a delightful small beach nestled in a bay that has calm, crystal blue-green water that is excellent for swimming and diving. Neighboring Coelhos beach has golden sand and very calm waters. They're perhaps the two most beautiful and tranquil beaches around Lisbon, although a bit more tricky to reach difficult to reach.
Finally Praia das Picisnas has a peaceful beach sheltered by pine forests and ideal for long walks by the sea - public transport is virtually non-existent though, so you'll need your own car to reach
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