Vesikko - similar submarineto UC-42
Coincidentally to the finding of UC-42 I was working in Heksinki, Finland where a very similar WW1 era submarine survives. She is the "Vesikko", a German type IIa submarine that was built in Turku, Finland for Germany. From these photos you may get a better feeling of what it was like aboard these submarines. Apologies for the poor quality of some of these photos when poor light compounded my own limitations.
Note that the Vesikko carries torpedoes in the forward section. The UC-42 on the other hand carried 6 mine tubes in the forward section, so you will need to imagine what the exact differences might have been. If anyone has plans of the UC-class minelayers I would love a copy!