Legii Valley Nature Reserve was established to protect waterbirds during nesting and also during migration. The area originally proposed for protection (1966) included 8 hectares of water surface, swamps, about 40 hectares of reed beds, meadows, old willow trees along the valley and a small woodland area, the nesting site for the Purple heron (Ardea purpurea)
and Spoonbill (Platalea leucorodia). The Nature Reserve "Legii Lake and Valley" was established by Decision No. 244/1966 of the Regional People's Council Cluj and stretched over an area of about 300 ha. In 1977 the area was again proposed for protection at national level, with an area of 26 ha, of which 6 ha of water and 20 hectares of reeds, with and additional 400 ha buffer zone encompassing grasslands, marshes and meadows, being the only wetland in the Fizeş Basin (apart from Pike Lake) preserved in a natural state. By Law No. 5/2000, the Legii Valley Nature Reserve surface is reduced to 13.5 ha, but was expanded again in 2004 at125 ha (O.U.G. 2151/2004). Despite the nature protected area status, in the 70s the woodland vegetation was already almost completely destroyed and the Legii creek was deepened and channeled in order "to regain land for agriculture." Consequently, the earth dike gave way, lake started to drain and the area to be invaded by reeds, so by 2008 there were only 2 ha of water surface left, in 2010 only a small central area of water surface remained and by the year 2014 the lake was completely invaded by reed. Ecosystem degradation triggered changes in the avifauna, the number of nesting birds has decreased significantly, from 24 species in 1967 to 13 in 2008 and 10 in 2014. Legii Lake was the only place in Transylvania where nestled the Spoonbill, so destroying this habitat the species has completely disappeared from Transylvania, and also the Red heron no longer nests anywhere Fizeş Basin.
Legii Valley Nature Reserve is situated in the Geaca County, about 60 km from Cluj-Napoca, and is accessible from County Road 109D.