Mixco Viejo, occasionally spelt Mixcu Viejo, is an archaeological site in the north east of the Chimaltenango department of Guatemala, some 50 kilometres to the north of Guatemala City and 4 kilometres from the junction of the rivers Pixcaya and Motagua. It is a moderate sized ruined city of the Postclassic Maya civilization.
The archaeological site and tourist attraction of Mixco Viejo was named after being erroneously associated with the Postclassic Poqomam capital referred to in colonial records by that name. The archaeological site has now been identified as Jilotepeque Viejo, the capital of the Chajoma Kaqchikel kingdom. To distinguish between the two, the ruins of the Chajoma capital are now referred to as Mixco Viejo while the former Poqomam capital is referred to as Mixco Viejo.
Coordinates 14°52'20.437" N -90°39'49.875" E