The first Christian conquest takes place in 1189. The Portuguese troops governed by D. Sancho I were assisted by a contingent of Crusaders en route to the Holy Land, which had landed accidentally in Lisbon. The ephemeral subjection lasted only two years, Al-Mansur endows the city with strong walls and water supply infrastructure. The last Christian conquest happens in the middle of the century. XIII. D. Afonso III, rushes to appoint a bishop to this episcopal see, and soon the city became capital of the Algarve. In the century. XV Prince Henry focuses in this metropolis, and actively promotes the participation of its people in the sea voyages of the Portuguese discoveries.