Guide to make continuous moving train?

I see maps like ctf_convoy which is a map with a moving train but what’s the guide on how to do it?

I think that the train isn’t moving, the ground is.

Yes I know that and I know it involves a repeating 3d skybox but how does he get the repeating effect?

No, nothing is moving. Everything is made with animated textures.

What about the cactus moving backwards? is that just a dynamic prop popping in at a certain amount of time?

It’s either a func_tracktrain, func_train or a prop_dynamic parented to one of the ladder. Just decompile the map if you want to know.

I am pretty sure it is a dynamic prop parented to a func_tracktrain with the same speed as the textures, teleporting to the starting track for loop effect.

Honestly, I have never seen that map; I was just assuming that since I’ve dealt with the subject before and most of the time they use animated textures.