The two historic mountain provinces of Beira Alta (Upper) and Beira Baixa (Lower) feature some of the most spectacular landscapes in the country, from upland plains of enormous boulders to towering mountain peaks. This harsh but beautiful landscape was home to the mighty warrior Viriatus, who used its remote wildness to his advantage when repelling the Romans. Later, as Portugal strived for nationhood, many of the towns near the disputed border with Spain acquired mighty castles, still in existence today. The ancient town of Viseu is the capital of Beira Alta province and the only place of any real size in the region. The fast east–west A25 links Viseu to the mountain-top town of Guarda – with Spain another 40km to the east – while to the north, between the highway and the Douro River, are the high-sited castle-towns of the planalto (or tableland). Some, like medieval, walled Trancoso, or the star-shaped fortress town of Almeida, are worth a day of anyone’s time. South of the main highway rises the Serra da Estrela mountain range, whose landscape is protected under the auspices of the Parque Natural da Serra da Estrela. Mountain villages, tumbling rivers and glacial valleys are linked by an extensive series of hiking trails, though there’s also road access to the major settlements, notably the enjoyable small town of Manteigas. The park’s southeastern boundary is flanked by the university town of Covilhã, handy for the winter ski fields and the ascent of Portugal’s highest mountain, Torre. South and east of Covilhã lies the sombre plain of the lower province, Beira Baixa, whose parched landscape has its own mysterious beauty, dotted with cork, carob and olive trees. Castelo Branco in the south is the provincial capital, but most tourist attention is centred on the ancient hilltop villages rising dramatically from the surrounding plains, notably Sortelha and Monsanto. There’s historic interest, too, in pretty Belmonte, halfway between Covilhã and Guarda, and in the extensive Roman remains at isolated Idana-a-Velha. Meanwhile, in the border hills and reservoirs of the Serra da Malcata, there are hiking, biking and wildlife-spotting opportunities.