Alvensleben Tunnel

The Alvensleben tunnelThe Alvensleben tunnel has its name after Albrecht Graf (1794 - 1858). He was appointed Prussian Minister of Finance in 1836 and at the same time had responsibility for the Mining Division.    The dead straight course to the passage occurrence (length 1546 meters
    The alignment of the tunnel on the kurkölnische castle Lahr
    The remarkably low gradient (1.5 meters per 1000 meters of lug length)
    The continuously introduced rose vault under the sole
    Sumpholes at regular intervals
    Vaulting in a constant elliptical shape in mountainous areas with insufficient stability
    Victoria shaft at 1200 meters lug length (attached laterally)
    Air or (light) hole for ventilationSummary:
     Construction time: 1835 - 1864
    Average propulsion per calendar day: 14.6 cm
    Length to the vein of the pit Louise: 1546 m
    Gradient: 1.50 meters to 1000 metersContact:
Tourist information of VG Flammersfeld
info@vg-flammersfeld.de
burglahr.de

The gallery is accessible to visitors at around 400 meters by prior arrangement.

Unfortunately I didn't have time to visit the tunnel.