In the tenth century, Countess Mumadona had a monastery built on her estate. The fact that it was the object of intense Moorish attacks led to the construction of a fortress to protect the monks and the Christian community. Thus was born the Castle of Guimarães. In the 12th century, with the formation of the Portucalense County, the Conde D. Henrique and D.Teresa came to Guimarães to have great works at the Castle in order to enlarge it and make it stronger. Tradition says that it would have been inside the Castle that the counts have fixed residence and probably there would have been born Afonso Henriques. Between the XIII and XV centuries several kings contributed to the improvement of the Castle, having after that time been abandoned, being very degraded until the 20th century, when it was classified National Monument.