The pirate’s treasure is, in this case, an isolated retreat on a wide, black-sand beach rather off the beaten track. Reach the cove by hiking through the Charco Verde [1] reserve or by getting off the bus at the entrance just beyond the community of San José del Sur, then walking 15 minutes or so from the highway, following the signs.
El Tesoro (tel. 505/8832-2429) is located just far enough off the beaten track to encourage the local wildlife to whoop it up for you. The view is excellent, as is the swimming and boating, and several readers claim they serve the best tasting fish on the island. Pay $25 for a cabana with air-conditioning and private bath, and $2 per person to camp with a $6 tent rental. Group discounts are available.
Links:
[1] http://www.moon.com/destinations/nicaragua/ometepe-and-rivas/la-isla-de-ometepe/moyogalpa/sights/reserva-charco-verde