The Tempisque River is Costa Rica's 3rd largest river and Guanacaste's largest river. It extends from the skirts of Orosi Volcano all the way to the Gulf of Nicoya. The river is 144 km in length and was used to float logs down to Chira Island to be loaded onto boats. 

The Friendship Bridge was built as a gift from the Taiwanese government, connecting the Nicoya Peninsula to the Puntarenas coast, significantly shortening travel time to San Jose. 

The river is important to many species, in particular those that make their habitat at Palo Verde. Sand is also extracted from the river by means of bucket, boat, shovel, cart and oxen. The oxen take the loaded cart to an area where they allow the sand to dry. This same sand has been used in the material to build may of the main roads in Guanacaste. 

Fishing is also a popular activity for the huge tarpon that can be caught.