Latvia has over 12,500 rivers, which stretch for . Major rivers include the Daugava River, Lielupe, Gauja, Venta, and Salaca, the largest spawning ground for salmon in the eastern Baltic states. There are 2,256 lakes that are bigger than , with a collective area of . Mires occupy 9.9% of Latvia's territory. Of these, 42% are raised bogs; 49% are fens; and 9% are transitional mires. 70% percent of the mires are untouched by civilization, and they are a refuge for many rare species of plants and animals.