It is bounded on the north by the Atlantic Ocean , on the east by the states of Rio Grande do Norte and Paraíba , on the south by Pernambuco state , and on the west by Piauí .
It shares borders on the east by the states of Rio Grande do Norte and Paraíba , on the south by Pernambuco state , and on the west by Piauí . Its northern border is the Atlantic Ocean .