Part of the Debub Wollo Zone, Kalu is bordered on the west by Dessie Zuria, on the north by Were Babu, on the south and east by the Oromia Zone, on the southeast by Argobba special woreda, and on the southwest by Abuko.
The administrative center for this woreda is Harbu; other towns in Kalu include Ancharo, Gerba, and Degan.
[1] Forested area includes Yegof forest, 180 square kilometres of native trees and plantations of exotic species covering the steep slopes of Mount Yegof northeast of Kombolcha, which regenerated after the 1973-1974 famine.
Pottery shards were recovered from tombs near Atatiya in Harbu, pointing to the presence of the Kingdom of Axum as far south as the area this woreda now covers.
The majority of the inhabitants were Muslim, with 98.73% reporting that as their religion, while 1.17% of the population said they practised Ethiopian Orthodox Christianity.