The country is crossed by rivers rising in Spain and flowing to the Atlantic; among them are the Douro, the Tagus, the Sado, and the Guadiana. The river valleys support agriculture, and vineyards are maintained in the Douro and Tagus valleys. On the lower hillslopes there are olive groves; grains are grown and livestock are raised on the flatter uplands as well as on the plains near the coast.
There are great variations in terrain and climate among the six historic provinces. Trás-os-Montes in the extreme northeast has a rigorous mountain climate, as have parts of Entre-Minho-e-Douro (officially Douro). Beira has the highest mountains of the country, the scenic Serra de Estrela, dotted with resorts. Estremadura, in W Portugal, has broad, alluvial plains, rising to cool and rocky uplands; along the Atlantic coast is a celebrated resort region, reaching to the town of Estoril, near Lisbon. Most of Alentejo has a Mediterranean climate; although much of its soil is poor, together with Estremadura it is the granary of Portugal. The southernmost of the old provinces, Algarve, resembles the northern shores of Africa; mountains curve across the north of the province down to Cape St. Vincent, the southwestern tip of Europe; citrus and almond groves and off-season vegetables thrive in the mild climate.
In addition to the capital, other notable cities are Oporto, Coimbra, Setúbal, Braga, Évora, and Faro. The majority of the Portuguese people are Roman Catholics of Mediterranean stock; Portuguese is the official language.