Reserva Esperanza Verde The Río San Juan & Islas Solentiname

Nestled on the Río Frío, roughly halfway between San Carlos and Los Chiles, is this private 50 sq km humid tropical forest reserve. Expect to see hundreds of bird species, three kinds of monkeys, fingernail-sized tree frogs and an array of rare orchids. You can do it in a day trip from San Carlos (US$30 per person, two-person minimum), including local transport, guide and trail access, which can be arranged through Hotel-Cabinas Leyko in San Carlos. Alternatively, you can spend the night in one of its simple, solar-powered rooms (per person full board US$50).