I can't see that this has been done before on search. I went there on Tuesday and it is excellent. I was staying in Belfast and the public transport route looked a bit complicated so I contacted Black Taxi Tours and they took me. There is an exhibition and a guided tour which lasts 1hour and costs £5.75. The tour starts with recruitment then it's as though you are arriving in France. I learned a lot and the young man doing the tour was very knowledgable. Recommended.