Sentrum (literally, Centre) was a borough (with the same name as a present-day neighbourhood). The borough was numbered 01, and its perimeter was from Store Lungegårdsvann and Strømmen along Puddefjorden around Nordnes and over to Skuteviken, up Mt. Fløyen east of Langelivannet, on to Skansemyren and over Forskjønnelsen to Store Lungegårdsvann, south of the railroad tracks.