Not far beyond San Antonio, the two entrance roads meet and begin a steady climb to the reserve. One kilometre beyond the junction is a campsite (US$7.50) run by Fidencio and Petronila Bol, who operate Bol’s Jungle Tours; Fidencio can guide you to several nearby caves. About 5km uphill from the campsite is the Mai Gate, a checkpoint with information about the reserve, toilets and drinking water. There are plans to levy an entrance fee, but for the moment all the guards do is write your name in the visitors’ book (to ensure against illegal camping).
Once in the reserve, pine trees replace the dense, leafy forest. After 3km a road heads off to the left, running for 16km to a point overlooking the Thousand-Foot Falls (US$2). The setting is spectacular, with thickly forested slopes across the steep valley. The waterfall is about 1km from the viewpoint, but try to resist the temptation to climb around for a closer look, as the slope is a lot steeper than it first appears.
Around 11km further on from the junction to the falls lies one of the reserve’s main attractions, the Río On Pools – a gorgeous spot for a swim. Another 8km from here and you reach the reserve headquarters at Augustine/Douglas Silva. You can camp here and the village store has a few basic supplies. The huge Río Frio Cave is a twenty-minute walk from Augustine/Douglas Silva, following the signposted track from the parking area through the forest to the main cave. Sandy beaches and rocky cliffs line the Río Frio on both sides as it flows through the cave.