It is located in the northwestern part of the country, as is the Guanacaste Conservation Area (ACG).
It integrates within its limits the entirety of the Nicoya Peninsula, between Playa Grande to the northwest and the mouth of the Tempisque River in the southeast and from the coast of the Nicoya Peninsula to the west to the Tilarán mountain range to the northeast; to the north and northeast to the volcanic mountain range of Guanacaste.