An earlier discussion was about multiple track tunnels, and various arrangements thereof. One aspect of discussion was two single side-by-side tunnels versus one double track tunnel.
I was wondering how many single track tunnels exist side-by-side in the prototypical world. The only image I can mentally bring up is the scene at the end of the movie "Defending Your Life" that shows all the trains taking people from the afterlife to their next lives going through many side-by-side tunnels.
Does such a multiple tunnel arrangement exist in the real world?
I ask because my layout has five parallel tracks going under a mountain. I'm thinking of using five side-by-side single tunnels. It doesn't look as bad as it sounds.