Beyond Guarda and the mountains lies the Beira Alta tableland, or planalto, with its ancient, scattered villages separated by mile after mile of boulder-strewn scrub. It’s a land of harsh winters, where even potatoes were hard to grow – in bygone days, roast or dried chestnuts were used as a substitute, plucked from the large trees that signal the entrance to many of the villages. Still, there’s a history here that’s central to Portugal’s identity, starting with the border castles that typify the eastern planalto, in particular the stunning star-shaped fortress of Almeida. Other castles and fortified settlements of particular interest are those at Castelo Rodrigo, to the north of Almeida, Castelo Bom and Castelo Mendo to the south, and Penedono and Marialva to the northwest. There’s a bygone wealth in the region, too, that sprang from the merchant trade of medieval Jewish settlements like Trancoso, which is easily the most attractive small town in the planalto. With a car, you could see the whole region in a couple of days, with the best overnight stops at Trancoso, Almeida or Marialva, with its upmarket holiday village.