WW 1 Forts defending Liege

The plan was to visit Fort Lancing first.  We heard this is the Fort the Germans used the “big Bertha” 420mm howitzer.  We get there early Sunday morning and we find out it doesn’t open until 1400.   Luckily I brought my ww 1 battlefield guide and a gps system.  We then decided to go to Fort Flamelle.  We get there and of course it is only open on Saturdays.  We did get to walk up and down the front of it though.  I got a couple pictures.