Also a part of the Guatuzos Reserve, this 5,000-hectare protected area is part of an effort to reforest and protect the overgrazed watershed of the Río Frío and the Río San Juan.

From the dock of Esperanza Verde and the military post walk 500 meters downstream to the Centro de Interpretación Ambiental Konrad Lorenz, and a row of six guest rooms with 20 beds ($40 pp with transportation and food); inquire about special rates for NGOs, students, and Nicas. The barren area immediately surrounding the guest facilities is uninteresting, but a 40-minute walk up the road brings you straight into the heart of the rainforest—monkeys, 200 species of birds, giant spiders, and potentially even pumas, you name it.

There are a total of three trails and numerous aquatic trips. Contact Leonel Ubau with FUNDEVERDE in Hotel Cabinas Leyko in San Carlos (tel. 505/2583-0354, fundeverde [at] yahoo [dot] es). Located 15 minutes from San Carlos, take any colectivo heading up the Río Frío toward Los Chiles.