The capital of PiauÃ is Teresina . PiauÃ has the shortest coastline of any of the non-landlocked Brazilian states at 66 km ( 41 mi ) , and the capital , Teresina , is the only state capital in the north east to be located inland . The reason for this is , unlike the rest of the area , PiauÃ was first colonised inland and slowly expanded towards the ocean , rather than the other way around .