The northwestern province of Guanacaste named after the large umbrella-like trees prevalent in the zone, encompass a vast area if diverse topography. From the boiling mud pots of Rincón de la Vieja Volcano, to the sun-drenched beaches of the Pacific coast, this corner of the country offers much to the adventurous traveler and sun worshipper. Santa Rosa and Guanacaste National Parks are vital protective areas for the Dry Pacific climatic zone. Santa Rosa is also a very important historic site and protects remains of structures dating from the colonial period and Costa Rica's struggles for independence. The seasonal lake of Palo Verde National Park attracts the largest concentration of waterfowl and wadding birds in Central America.