Olho d'Água is a popular urban beach on the northern coast of the island, a bit quieter than Calhau and with a slightly more local character. The name — "eye of water" — refers to a freshwater spring that once emerged near the beach, though you won't find it today. The beach is long and backed by a good selection of beach bars and restaurants.
On weekday mornings, Olho d'Água is almost empty and perfect for a run or a swim without crowds. On weekend afternoons it fills up with family groups and volleyball games. The kiosk nearest the main entrance does a reliable tacacá — the indigenous shrimp soup that's another Maranhão signature dish — on weekend mornings.