Founded in 997 by Viking king Olav Tryggvason, it was first named Nidaros (still the name of the cathedral), a composite word referring to the city's location at the mouth of the Nidelva River. Today, it's Central Norway's largest (and Norway's third largest) city, with a population of 150,000. The wide streets of the historic city center remain lined with brightly painted wood houses and striking warehouses. But it's no historic relic: it's also the home to NTNU (Norwegian University of Science and Technology) and is Norway's technological capital.