The top half is pointed straight at the viewer while the bottom half has the tilt to the left. This really ruins my attempts to view it as a tunnel.
The way you drew the top of the tunnel makes it look flat, having to depth. What you could do is make ringed section, little arches that go toward the train. Make the closer ones look brighter too.
Um, yeah I would've needed the title too. :/
Well on the light, you could make the rays more defined, not blurred. Then taper them off. maybe add a light blue tint around the edges of the glow, or yellow, just not regular white, since it's pretty bland and the image has enough grayscale.
Also, you should draw tracks that get smaller the closer to the train to you, maybe do lights along the roof of the tunnel at intervals that also get smaller the closer to the train it is. Maybe even draw a flat panel running alongside the top of the tunnel so that you can make out any curves.
It's hard drawing on such a large canvas. what did you draw it with? Mouse or tablet? Just curious. Oh, and make the tunnel part go to all the edges of the drawing, so it gives the effect of the viewer actually being inside the tunnel as opposed to just....viewing it.
The two windows on the tunnel look a bit like eyes too. Makes the whole thing look ghoulish.