Mainz-Kastel station is situated on the Frankfurt–Wiesbaden line in Mainz-Kastel, now a suburb of Wiesbaden, in the German state of Hesse. It was opened as part of the Taunus Railway, which was opened in 1839/40. The station was opened as part of the last stage of construction of the line to Wiesbaden and was opened on 19 May 1840.