 However, the party was attacked by Mapuche warriors at the Battle of Quilacura.Realizing that it would be impossible to proceed in such hostile territory with so limited a force, Valdivia wisely elected to return to Santiago shortly thereafter, after finding a site for a new city at what is now Penco and would become the first site of Concepción.Still, Valdivia managed to subdue the country between Santiago and the Maule River.