Comboios de Portugal (CP) commuter trains travel the entire Estoril Coast, with departures every 15 to 30 minutes from the waterfront Cais do Sodré station in Lisbon, west of the Praça do Comércio. The scenic trip to Estoril takes about 30 minutes, and four more stops along the seashore to the end of the line at Cascais. A one-way ticket to either costs €2.25. Trains from Lisbon's beautiful Rossio station depart every 15 minutes to Queluz (20 minutes) and on to Sintra (40 minutes). One-way tickets cost €1.65 to Queluz and €2.25 to Sintra.
Fertagus trains from Lisbon's Roma–Areeiro, Entrecampos, Sete Rios, and Campolide stations head south via the Ponte 25 de Abril crossing the Tagus River. Passengers on the double-decker railcars benefit from pleasant views and soothing music on the way to Setúbal, a journey of around an hour. Tickets cost €4.55 one way.
From June to September, the Transpraia narrow-gauge railway runs for 8 km (5 miles) along the Costa da Caparica from the town of Caparica to Fonte da Telha, making 20 stops at beaches along the way. A one-way ticket to the end of the line costs €3. The "mini train" opens up stretches of coastline that are otherwise inaccessible without a car, and even makes a call at a nudist beach.
Comboios de Portugal. 707 210 220; www.cp.pt/passageiros.
Fertagus. 211 066 363; www.fertagus.pt/.