a while ago i visited fort "North of Spaarndam" ... a still in original shape fort ... was in use as munitie storage till 1970 ! ... located near the North Sea Channel that connects the port of Amsterdam with the North Sea ...every warship that visited Amsterdam in those days had to store their munition at this fort ... al so called "smal railroad " transported the munition from the ships to the fort !!
after abbandoned by the Navy they cut of the electricalpower ...so my friends there use a generator the get light ...and for the atmosphere they use candles !!
while cleaning the fort they discoverd many original items ... some great wall paintings from different time periods ..this fort was in use by the German forces during WW2 ... and by the Dutch forces during WW1 !