Sonnenberg is a borough of Wiesbaden, the capital of the state of Hesse, Germany. Formerly an independent municipality, Sonnenberg was incorporated into Wiesbaden on 28 October 1926. The borough has approximately 8,000 residents.Sonnenberg is located in the northeast of the city. Its historic center is located in the foothills of the Taunus in the narrow valley of Rambach.