The la Coupole was never used in action by the Germans, indeed it was never finished. As with its sister site, the giant ‘Blockhouse’ at Eperleques, allied bombing and not least the ground invasion put paid to the scheme.
The entry tunnel, which would originally have a train track running along its length. The original train line (la Couple, was built on a spur) is still in operation today:


It’s worthwhile using the interactive headsets, as you walk around.
Leaving aside the V-weapons’ intent, what struck me was a simple explanation of the financial cost of the damned things, let alone the human cost of building them and, not least, putting them out of action forever:





On thing that did amuse me, is that the Germans made the visitors’ lift, which carries you up inside the domed roof:
