Calamagan derived its name from the local word “ Kalamag Ka”, means walk to the other side.
Dubbed as a “barangay within a barangay”, Calamagan is created before the creation of Barangay Lengaoan and Barangay Sebang carved from Bangao. It shares boundaries with Bangao and is accessible thru Bangao from the Halsema Road. It is the smallest barangay in terms of land area and population resources. Calamagan is home to mainly kankan-eys engaged in vegetable farming as their primary occupation.
Calamagan is composed of 6 sitios namely: Camanbeey, Calamagan Proper, Daligdig, Macogcog, Panapsapan, and Alam-am.