Gudbrandsdalen (; ) is a valley and traditional district in the Norwegian county of Innlandet (formerly Oppland). The valley is oriented in a north-westerly direction from Lillehammer and the lake of Mjøsa, extending toward the Romsdalen valley. The river Gudbrandsdalslågen (Lågen) flows through the valley, starting from the lake Lesjaskogsvatnet and ending at the lake Mjøsa. The Otta river which flows through Otta valley is a major tributary to the main river Lågen. The valleys of the tributary rivers such as Otta and Gausa (Gausdal) are usually regarded as part of Gudbrandsdalen. The total area of the valley is calculated from the areas of the related municipalities. Gudbrandsdalen is the main valley in a web of smaller valleys. On the western (right hand) side there are long adjacent valleys: Ottadalen stretches from Otta village, Gausdal some from Lillehammer and Heidal some from Sjoa. Gudbrandsdalen runs between the major mountain ranges of Norway including Jotunheimen and Dovrefjell–Rondane. Together with the Glomma river and the Østerdalen valley, the river Lågen and the Gudbrandsdalen valley form Norway's largest drainage system covering major parts of Eastern Norway. Gudbrandsdalen is home to Dovre Line railway and the European route E6 highway. The valley is the main land transport corridor through Eastern Norway, from Oslo and central eastern lowlands to Trondheim and Møre og Romsdal. The valley is divided into three parts: Norddalen (Northern valley; the municipalities of Lesja, Dovre, Skjåk, Lom, Vågå and Sel), Midtdalen (middle valley; the municipalities of Nord-Fron, Sør-Fron and Ringebu), and Sørdalen (Southern valley; the municipalities of Øyer, Gausdal and Lillehammer). The municipalities within the valley fall under the Vestre Innlandet District Court. Until 2016, the valley was also a police district. The Gudbrandsdalen district covers about 60% of the former Oppland county. The main character in Henrik Ibsen's play Peer Gynt was inspired by a real or legendary person living in the valley in the 18th or 17th century. Ibsen travelled through the valley in 1862 and collected local stories, legends and poems. Ibsen also made drawings from his trip, including "Elstad in Gudbrandsdalen". Etymology The name Gudbrandsdalen means 'the valley/dale of Gudbrand'. Gudbrand (Old Norse Guðbrandr) is an old male name compounded of guð, 'god' and brandr, 'sword'. The name may be derived from a chief (hersir) called Gudbrand. According to Snorri Sturluson the district was also referred to as i Dalom ("in the valleys") because of the many