Mixco Viejo lies on a plateau in the valley of the Motagua River. It was the ancient capital of the Pokomam Maya group. Its palaces and temples show that the city was not only a ceremonial center but also a military center, for the warring class who inhabited it. Its impressive location, between deep ravines, was not by chance. It served as an almost impregnable natural fortification, which took Pedro de Alvarado more than three months of siege to conquer.