The Río San Juan  carries the waters of Lake Cocibolca to the Caribbean through a lush landscape of extensive nature reserves and broad cattle ranches. Five hundred years ago, the Spanish, intent on piercing the Central American isthmus, focused their efforts on the Río San Jua], which nearly connects the two sides of Central America, save a thin strip of land.
In 1524, Hernán Cortés wrote King Carlos I of Spain, “He who possesses the Río San Jua] could be considered the owner of the World.” The strategic and economic importance of this region has not diminished since.
The principal settlement in the area, San Carlos  is transforming from edgy port town to quaint destination and you’ll inevitably pass through it on the way to various adventures. The town is thick with itinerants, rowdies, farmers, fishers, swindlers, and you.
Offshore, the Solentiname Archipelago  is a quiet group of islets as pertinent to the revolution years as to Nicaragua’s prehistoric past, and a center of production for some of the country’s most gorgeous paintings.
Or, take a wooden boat down the river towards the Atlantic, a sun-baked ride back through time. El Castillo , one of Spain’s most permanent colonial legacies, remains little changed from the 17th century and the days of marauding pirates. From there downstream fishing village follows pasture follows rapids until you reach San Juan de Nicaragua , the little town where it all began and where it all ends, remote and untamed.
It’s not easy to get to the Río San Juan , and tougher still to get around, but everyone agrees that things are rapidly changing for the better, due in large part to a $14 million tourism development plan called La Ruta del Agua, the effects of which you’ll see as soon as you step onto the refurbished dock or recently paved airstrip at San Carlos .
This region isn’t part of the casual traveler’s itinerary, but if you can invest a little more time than usual, the dramatic landscapes and remoteness of this region will impress you, and the tourism potential here is enormous.