The Sierpe River is a large, slow moving river that goes from the Sierpe Lagoon ( along the Panamerican Highway ) to the Pacific Ocean, between the Terraba River Mouth and the Osa Peninsula. The wide river is the main transport and communication route in the area, connecting the town of Sierpe with places in the Osa Peninsula, including Drake Bay, Isla Violin, Guera, Playa Ganado and the ranger station of San Pedrillo and Sirena. There are public boatds departing from Sierpe village daily, at 11 AM and at 3 PM. It takes around 1 hour from Sierpe to Drake Bay, a beautiful trip, since the river goes through the large tropical mangrove forests of the Sierpe Terraba Delta.
The river is also a highlight from the natural point of view, since it is surrounded by a large mangrove forest, with abundant canals and waterways that create not only a haven for the endangered mangrove vegetation, but also animal species that reside in its forests, including monkeys, rare snakes, amphibians, insects, and many unique species of birds, fish and mollusks.