How to build a Double track tunnel? Login | Register | Lost your password? Home › Forums › General Discussion › How to build a Double track tunnel? This topic has 0 replies, 1 voice, and was last updated 7 years ago by gax. Viewing 1 post (of 1 total) Author Posts September 8, 2014 at 13:18 #6046 gaxParticipant I always get a terrain alignment collusion. Author Posts Viewing 1 post (of 1 total) The forum ‘General Discussion’ is closed to new topics and replies.