[1] Breakthrough was achieved on 15 March 1896, and construction finished in August 1896.

[1] The tunnel was opened to traffic on 1 June 1897 along with the rest of the Thalwil–Zug railway line.

[5][6][7] On 5 February 1923, electrification of the railway line, including the tunnel, was completed.

[5] The segment leading through the two tunnels constitutes a single-track section on the Thalwil–Arth-Goldau railway.

[3][7][8] The proposed phase II of the Zimmerberg Base Tunnel aims to resolve the bottleneck formed by the single-track sections and to allow for faster traffic on the Thalwil–Arth-Goldau railway.