In the west of the country, these lowlands consist of a broad, hot, fertile plain. Punctuating this plain are several large volcanoes of the Cordillera Los Maribios mountain range, including Mombacho just outside Granada, and Momotombo near León. The lowland area runs from the Gulf of Fonseca to Nicaragua's Pacific border with Costa Rica south of Lake Nicaragua. Lake Nicaragua is the largest freshwater lake in Central America (20th largest in the world), and is home to some of the world's rare freshwater sharks (Nicaraguan shark). The Pacific lowlands region is the most populous, with over half of the nation's population.