Castles in Portugal

Castles in Portugal were crucial components of the military across history. The Portuguese learned the art of building fortifications from the Romans and the Moors. The Romans, who ruled and colonized the territory of current-day Portugal for more than four centuries, built forts with high walls and strong towers to defend their populations. The Moors, who invaded the Iberian Peninsula in the year 711, brought new stonework and heavily fortified gates to the peninsula.

Portugal has well-defined geographic boundaries, with the Atlantic Ocean to the south and the west, and rivers and mountains to the east and north. It occupies the westernmost portion of the Iberian Peninsula, and is about the size of the American state of Indiana. The country is a place of topographical contrasts as well, making its defense difficult. The areas around Porto in the north are hilly and green, with fertile river valleys and a rocky coast. The green mountains turn less fertile as they spread to the east, and become mountainous towards the south to the Beiras. Along the coastal Beiras, the topography becomes hillier, with pine forests and a sandy coast. In the central region, the area around the capital of Lisbon, is known for its white rocks, olive fields, and open spaces, while the Tagus basin divides the nation in half, with the yellow hills and cattle fields of the central region on the north bank and the beginnings of the Alentejo to the south. The Alentejo is a vast golden plain that extends south to the red cliffs and green hills of the Algarve, an area markedly influenced by its affinity with Africa, as much as Europe.

These conditions made the defense of Portugal difficult, and the region was marked by eras of fortification building. Unlike many of their European counterparts, Portuguese castles were heavily influenced by the master-builders of Rome and Northern Africa. Even the early Celtic tribes of Portugal, the early Lusitanians, already fortified their villages within simple stones walls by this time. The Romans, who occupied Portugal after this period, for the next 400 years, then built forts with high walls and strong towers to defend their towns. The Romans were the first to bring in organized military outposts in order to guard their domains. These outposts were usually built on existing fortified castros or defensible Neolithic/Paleolithic strongholds in the hills. But, the Romans gradually built their centres based on their trade and/or commercial needs, and abandoned many sites for places along rivers or lowland agricultural settlements. The outposts that remained continued to serve as sentries or outposts, while some points evolved into larger towns or cities that survived long after the Romans had retreated.

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Wikipedia