Cascais

Eighteen hectares of former aristocratic gardens turned into a public park in central Cascais, with duck ponds, free-roaming peacocks, century-old pines and the Castro Guimarães palace. Leash required; open every day except Monday.

Three-kilometre flat seafront promenade linking Cascais marina to Estoril casino, hugging the Atlantic the whole way. Leash required; periodic water fountains; no shade between 11:00 and 17:00 in summer.

Spectacular sea arch and blowhole where Atlantic swells crash into a partially-collapsed cave, 1.5 km west of the marina. Paved trail with viewing platforms, leashed dogs welcome; low railings on the cliff edges.

16th-century coastal fortress restored as a cultural complex with art galleries, the Pestana Pousada hotel and a courtyard restaurant. Ramparts, bastion walks and central square freely accessible; leashed dogs welcome outdoors.

Vast Atlantic surf beach inside the Sintra-Cascais Natural Park, 9 km north-west, famous for its wind. The unconcessioned northern and southern ends accept leashed dogs year-round; concessioned sections ban dogs from 1 May to 30 September.

Striped blue-and-white lighthouse perched on the rocks behind Praia da Conceição, with adjacent museum and a small but spectacular cliff-edge garden. Outdoor garden and cliff path accessible to leashed dogs; museum interior not permitted.