Estrema-Dura is a province and former region of central west Portugal, including parts of the present day districts of Lisboa, Setúbal and Leiria. The agricultural heart of the province is to the west, around Alcobaça, where the Mediterranean climate supports the production of olives, vines and fruits, wheat, maize and vegetables. The northern uplands provide grazing for sheep and goats with subsequent production of cheese. Low-lying valleys provide marshy ground for rice. Like Extremadura in Spain, Estremadura was named as the "extreme" border of Christendom during the Reconquest.
