HOP ON A BIKE (it’s less than $5 a day to rent one at the station) to explore Lisbon’s former fishing village of Cascais. Easy access to bikes is one of the eco-friendly features that earned this lively beach enclave the European Union’s coveted QualityCoast Gold award in 2016, naming it one of Europe’s most sustainable coastal tourism destinations.

Green-minded travelers will find more to like about Cascais, from its carefully protected beach dunes to its twice-weekly market dedicated solely to locally produced foods. Rehab of the extensive Cresmina-Guincho coastal dunes began in 2010, and today you can access beaches and follow wooden walkways through 90 restored acres, learning about dune flora and fauna from signboards and at the new Interpretation Center. The self-sufficient Environmental Interpretation Center at nearby Pedra do Sal is the first Zero Energy building in Portugal.

The dunes begin just beyond the dramatic Boca do Inferno (Mouth of Hell), a 20-minute walk from central Cascais, where the high Atlantic surf crashes noisily into caves in the jagged cliff. Farther north, at the beautiful sands of Guincho, these waves create one of Europe’s best surfing beaches.

King prawn at the market © LEVAI GABOR | DREAMSTIME.COM

Fishermen gather at their own colorful beach, not far from the daily market where you can watch the catch auctioned off in the late afternoon. Best of all, almost every restaurant in town — and there are plenty — specializes in serving fresh seafood. Choose from traditional or innovative preparations of ocean-fresh sea bass, bream, Cascais sole, sardines, shrimp, crab or crayfish. These go well with red or white Colares wine, a local DOC whose vineyards are protected by the coastal dunes.

Life in Cascais revolves in one way or another around the sea and the spectacular coast, whether it’s the wave-shaped mosaic of its paving stones, the little Museu do Mar (Museum of the Sea) or the sun-drenched beaches where children build sandcastles.

Martinhal Cascais, set handily between the two championship golf courses of Quinta da Marinha and Oitavos Dunes, is a new luxury hotel that caters especially to children. This makes Cascais a good choice for families, close enough to central Lisbon for easy sightseeing but with the relaxed vibe of a beach town.