sentences:  Río Azul is situated to the southeast of the Azul river and its apogee dates to the Early Classic period (c. AD 250–600).The earliest major architecture dates to around 500 BC, in the Late Preclassic period (c. 350 BC – AD 250).In the late 4th century AD Río Azul was dominated by the city of Tikal and its great central Mexican ally Teotihuacan.