Approximately 900 people live in Tretten, 30 kilometers north of Lillehammer. In the village farming is a predominant factor, such as production of cattle and swine, as well as cultivation of forests, grain and grass. In addition, cheese making industry, stonecutting and businesses in tourism and other services are found in Tretten.
In the past the village centre was loctaed farther up in the valley than today, around the farm Prestegarden. A stone chuch was erected here in the late 1200s, and the ruins of it is today hidden under Kjørkehaugen. In the Middle Ages Tretten had its own parish, but after the Black Plague (1348/9-1350) the village could not hold its own priest, and Tretten became annexed by the Øyer parish - which it has been since.
In 1894, construction began on Tretten station. The station was the final stop of the Hamar-Sel railway from 1894 to 1896. The construction boosted the emergance of a hotel, general store, entertainment places, homes and a village hall.
During the Second World War heavy fighting between British and German soldiers took place at Tretten. On 23 April 1940 British infantry brigades attempted to stop the German forces advancing north in Gudbrandsdalen, but had to retreat after heavy German fire.