There were five prominent dominions of the Kalinga Ganga family in initial days: Kalinganagara (Srikakulam), Svetaka Mandala (Ganjam), Giri Kalinga (Simhapur), Ambabadi Mandala (Gunupur, Rayagada) and Vartanni Mandala (Hinjilikatu, Ganjam).
Eastern Ganga Dynasty

ThenTriKalinga defination was different.
In the he heartland of the Eastern Ganga Dynasty had3 parts of Kalinga namely, Daksina Kalinga (Pithapura), Madhya Kalinga (Yellamanchili Kalinga or Visakhapatnam), Uttara Kalinga (districts of Srikakulam, Ganjam, Gajapati and Rayagada).

During the rule of Vajrahasta V from 1038-1070 A.D the Gangas started playing a prominent role from the southern horizon of the already weakening later Somavanshi kingdom.
Eastern Ganga Dynasty

He introduced the Anka year of calculation system for the regnal years of the kings and this continued as a standard norm for future kings of ancient Odisha.
Eastern Ganga Dynasty

One of his predecessors had tried to unite the Ganga dominions in the Kalinga Dandapat area unsuccessfully. Vajrahasta V had not only united the Ganga domain but also had defeated the Somavanshis in his northern frontiers.
Eastern Ganga Dynasty