This paper discusses the main archaeological evidences recovered during excavations at the archaeological site of Chaupisawakasi, located in the Quilcamayo-Tintiri River Valley, Department of Puno, Peru. This valley is located in the northern part of the Titicaca Basin. Our research indicates that the site was built by social groups associated with the Pukara society (ca. 500 BC-AD 400). We conclude that Chaupisawakasi is a Pukara-affiliated political and ceremonial center characterized by a monumental sector that dates to at least the 1st century BC. In this paper, we discuss Pukara expansionary strategies in this valley and we review the implications of this data for other areas of the northern Titicaca region during the Upper Formative Period.