The board of county commissioners of any county in this state in its discretion, after the purchase or lease and the improvement of the land for fairground purposes as provided for in section 35-65-111, may appoint some person to look after, operate, and conduct county fairs on said fairgrounds during each year; or the said board of county commissioners may in its discretion rent or lease the said fairgrounds and improvements thereon for suchrental and for such term or period of time as it deems reasonable and proper to any corporation not for pecuniary profit duly organized under the laws of the state of Colorado for the purpose of conducting, operating, and holding a county fair for the promotion of all mechanical and industrial products and agricultural, horticultural, livestock, and other products and exhibits and also for the purpose of conducting races, sports, and other entertainment usually given at county fairs.