Costa Rica also borders Nicaragua to the north (309 km or 192 mi of border) and Panama to the south-southeast (639 km or 397 mi of border). In total, Costa Rica comprises 51,100 square kilometres (19,700 sq mi) plus 589 square kilometres (227 sq mi) of territorial waters.
The highest point in the country is Cerro Chirripó, at 3,819 metres (12,530 ft); it is the fifth highest peak in Central America. The highest volcano in the country is the Irazú Volcano (3,431 m or 11,257 ft). The largest lake in Costa Rica is Lake Arenal.
Costa Rica also comprises several islands. Cocos Island (24 square kilometres / 9.3 square miles) stands out because of its distance from continental landmass, 300 mi (480 km) from Puntarenas, but Calero Island is the largest island of the country (151.6 square kilometres / 58.5 square miles). Over 25% of Costa Rica's national territory is protected by SINAC (the National System of Conservation Areas), which oversees all of the country's protected areas. Costa Rica also possesses the greatest density of species in the world.