The second largest stretch of intact primary forest in the country, the Indio-Maíz Biological Reserve is a vast wilderness and a hugely important rainforest ecosystem with incredible biodiversity.
Indio-Maíz Biological Reserve Wildlife Sanctuary
While much of the reserve is restricted, it is possible to visit certain parts. In 2018, horrific fires caused by outsiders, who were illegally clearing the forest for use as farmland, destroyed huge areas of old-growth forest and the reserve will take decades to recover.
At the confluence of Rio Bartola and Rio San Juan, the ranger’s office manages a 3 km hiking trail that winds through the towering trees of the reserve.
A local guide is required to enter and most visitors come in a packet from El Castillo. Another 20 minutes downstream by boat is the entrance to the reserve at Aguas Frescas, where the scenery is similar but there is a slightly longer and more challenging trail.
While Aguas Frescas was once less visited and therefore attracted more wildlife than the Bartola section, both trails are now very popular and choosing a section depends mainly on how far you want to hike.
Note that despite the entrance fees charged to use the facilities, both trails are in very poor condition, with deep mud as the norm in many parts, so bring suitable footwear and long pants.
About an hour further on from the mouth of the Sarapiqui River, the San Juan Delta begins to meander through the wetlands, meeting the almost-as-huge Colorado River.
The birding gets increasingly interesting and the fishing even better, but be aware that you have officially entered bull shark territory, so no swimming.
When you finally enter the expansive San Juan del Norte Bay, you’ll notice the rusty old dredge owned by the Cornelius Vanderbilt Transit Company, which kept shipping lanes open for would-be gold prospectors en route to San Francisco.
The dilapidated pier to the south marks the entrance to what remains of Greytown, founded at what was then the mouth of the San Juan River, now a sandy expanse of dry land.
After crossing the bay to the mouth of the remarkable Indian River, you’ll reach San Juan de Nicaragua, where you can explore blackwater streams, hidden lagoons and thick jungle within the wide reach of the Indian-Maize.