Hessdalen is a village in the municipality of Holtålen in Trøndelag county, Norway. Hessdalen also refers to the long valley that surrounds the village. Hessdalen is located in the central part of the village, approximately south of the city of Trondheim, approximately north of the mining town of Røros, and about southwest of the village of Renbygda. About 150 people live in the village and surrounding valley. Hessdalen Church is located in the village of Hessdalen and the lake Øyungen lies about southwest of the village. The Hessdalen area is known for the occurrence of unexplained aerial luminous phenomena called the Hessdalen lights. The phenomenon is monitored by the Hessdalen AMS. Name The first element is the name of the local river Hesja and the last element is the definite form of dal, which means "dale" or "valley". References Holtålen Valleys of Trøndelag Villages in Trøndelag