Rørosⓘ or Plaassja (Southern Sami) is the administrative centre of Røros Municipality in Trøndelag county, Norway. The town is located along the river Hyttelva and along the Rørosbanen railway line, about 10 kilometres (6.2 mi) south of the village of Glåmos and about the same distance north of the village of Os i Østerdalen in neighboring Innlandet county.
The 3.31-square-kilometre (820-acre) town has a population (2024) of 3,909 and a population density of 1,181 inhabitants per square kilometre (3,060/sq mi).
The mining town of Røros is sometimes called Bergstaden, which means "the rock town", due to its historical copper mining. It is one of two towns in Norway that were historically designated as a bergstad or "mining town", along with the "silver-town" of Kongsberg in Buskerud county. The bergstad formerly had special rights as a mining town, slightly different from those of other towns/cities in Norway. Because of this, it is sometimes referred to as a town, despite the actual classification being a bergstad.
Many modern-day inhabitants of Røros still work and live in the characteristic 17th- and 18th-century buildings which have led to its designation as a UNESCO World Heritage Site in 1980. The town of Røros has about 80 historic wooden houses, most of them standing around courtyards. Many retain their dark pitch-log facades, giving the town a medieval appearance. There are also two churches in the town. The large and historic Røros Church and the relatively new, but unique-looking Røros Chapel.