Sisupalgarh or Sisupalagada is situated in Khurda District in Odisha.
It is now in ruins except the imposing towers and pillars around the fort near the Daya river.
It used to be the capital of ancient Kalinga. It is identified with Kalinganagara of Kharavela and Tosali of Ashoka. It is one of the largest and best preserved early historic fortifications in India, with the earliest occupation both inside and outside the later site´s northern rampart around 7th to 6th centuries BCE.
It is the oldest place as Athens with a similar estimated population of 25,000 during that period.
Still, some excavations are taking place and there are no sign boards to update the important historical moments in the place – like Kalinga war of Ashoka. Do research before you visit the place.