On 12 February 1541 Valdivia officially founded the city of ''Santiago del Nuevo Extremo'' (''Santiago of New Extremadura'') near the Huelén, renamed by the conqueror as Santa Lucia. Following colonial rule, Valdivia entrusted the layout of the new town to master builder Pedro de Gamboa, who would design the city grid layout. In the center of the city, Gamboa designed a Plaza Mayor, around which various plots for the Cathedral and the governor's house were selected. In total, eight blocks from north to south, and ten from east to west, were built. Each solar (quarter block) was given to the settlers, who built houses of mud and straw.