Rennebu is a municipality in Trøndelag county, Norway. It is part of the Orkdalen region. The administrative centre of the municipality is the village of Berkåk, located along European route E6. The majority of the population lives in the villages of Berkåk, Innset, Stamnan, Ulsberg, Voll, and Nerskogen. The municipality is the 123rd largest by area out of the 356 municipalities in Norway. Rennebu is the 257th most populous municipality in Norway with a population of 2,443. The municipality's population density is and its population has decreased by 4.9% over the previous 10-year period. The municipality of Rennebu was established in 1839 when it was separated from the municipality of Meldal. Initially, the population was 2,368. On 1 January 1966, the parish of Innset (population: 420) was transferred from Kvikne municipality (and also from Hedmark county) to Rennebu (and Sør-Trøndelag county). Then on 1 January 1970, the Garlia area (population: 5) was transferred from Tynset (and Hedmark county) to Rennebu (and Sør-Trøndelag). On 1 January 2018, the municipality switched from the old Sør-Trøndelag county to the new Trøndelag county. The municipality (originally the parish) is named Rennebu (Rennabú). The first element is, maybe, the plural genitive case of renna which means "journey", "march", or "road". Probably because two old important roads cross the municipality: one follows the Orkla river from the Orkdalsfjord (part of the Trondheimsfjord) to the village of Berkåk where it connects with the road from the Gudbrandsdalen valley and Oppdal to Gauldalen and Trondheim (today the European route E6). The last element is bú which means "rural district". The coat of arms was granted on 19 February 1982. The official blazon is "Or, a pall reversed couped gules" (I gull ein svevande omvend raud gaffelkross). This means the arms have a field (background) has a tincture of Or which means it is commonly colored yellow, but if it is made out of metal, then gold is used. The charge is a Y-shaped design in red.