Travel along the shores of Lake Nicaragua, the second largest body of freshwater in the Americas, using the new yet still little-used road through rolling cattle country and small cowboy towns, to San Carlos on the south-eastern shores of the lake.
The liveliest part of quiet and somewhat ramshackle San Carlos is down by the pier: ferries and private launches jostle for space with fishing boats. The roads from the north end here: to travel east to the settlements along Rio San Juan you have to take a boat.
You’ll embark on a 90-minute river journey by river. The banks are initially farmed, with fields of maize and grazing cattle punctuated by small jetties and rural homes. However, as you travel downstream, the vegetation gradually becomes dominated by natural tropical forest. There’s plenty of wildlife to be seen: scores of snowy ibis alight upon the branches overhanging the water and you may spot monkeys swinging through the taller trees or a caiman lazing on naked logs.
You turn a bend in the river to be greeted by a spectacular and unexpected sight: on a rare hilltop a vast, stone-built Spanish fortress glowering over a series of white-water rapids and the squat, wooden stilted houses of the quirky little port El Castillo.
In the evening, go searching for caimans by boat under the moonlight, accompanied only by a specialist guide. As you glide for 90 minutes through the darkness, a journey orchestrated by the nocturnal sounds of the rainforest, the guide will be using a spotlight to reflect the beady red eye of caimans (alligators) at repose in the tropical vegetation along the water's edge.