Saint Lucas Island is a continental island located in the Gulf of Nicoya of Costa Rica. It has an extension of 472 ha; whose height oscillates between 0 and 220 meters above sea level, and is located in the dry tropical forest life zone.
The average annual precipitation registered in Puntarenas is 1596 mm; and the Refuge is located in a region that has two distinct climatic seasons: the dry season from December to April, and the rainy season from May to November. The average temperature ranges between 25 to 30 degrees, the high between 30 to 35 degrees while the low between 20 to 25 degrees.
According to the political-administrative division of the country, the Isla San Lucas National Park is located in the Central Canton of the Province of Puntarenas.