The Sado estuary near Setúbal is home to Portugal's only resident population of bottlenose dolphins: around 27 individuals, monitored since 1981, one of just three resident estuarine colonies in Europe. On this private full-day tour from Lisbon you join a licensed dolphin-watching boat that follows the official code of conduct, with sightings on roughly 95% of departures.
The day is built around the boat, not a checklist. After pickup at your Lisbon hotel, cruise port or the airport, stop at the Cristo Rei sanctuary for the classic view over the city and the 25 de Abril bridge, then head south across the peninsula for your boat trip on the Sado. Back on land, enjoy free time in Setúbal, where the local lunch specialty is choco frito, crispy fried cuttlefish (own expense). On the return, visit the castle above Sesimbra for clifftop Atlantic views before heading back to your accommodation.