Du-Ku or dul-kug [du6-ku3] [1][2] is a Sumerian word for a sacred place.
There is no mention of nor association with the term "holy", and instead it represents a cultic and cosmic place.
The location is otherwise alluded to in sacred texts as a specifically identified place of godly judgement.
[5] The hill was the location for ritual offerings to Sumerian god(s).
[7] Nungal and the Anunna dwell upon the holy hill[8] in a text written from Gilgamesh.