sentences:  Population levels reached their height here during the Late Classic (AD 600-900); during this era the rulers of La Joyanca embarked upon an ambitious building project in two areas, dubbed the Plaza Principal and the Grupo Guacamaya.The Grupo Guacamaya, a complex of vaulted rooms and corridors, may have served as their palace and thus the seat of local government.Following this prosperous era, the site, like most of its Classic period contemporaries, underwent a dramatic collapse.