Puerto Rico doesn’t have many mountain lakes, but Lago dos Bocas is one of its most captivating, hemmed in by karst cliffs draped with tenacious fern-green vegetation. Created as a reservoir in 1942, its three snaking arms cover 25 square miles, making it the third largest lake in Puerto Rico. You might see a few pelicans on the water, but other than soaking up the impressive scenery, the main reason for a visit is to dine at one of several inviting lakeside restaurants, only accessible by boat and open only on weekends.