tunnel system

It depends if you want to be able to walk in it.... I have seen 4ft; but ours is a little over 6.

Would make it so you can stand up and walk in it with gates or doors every so often to keep the deer from turning back if you make it to short you will be bent over for only a couple deer that wouldnt be bad but if you have a lot to run through it gets hard on your back and if 1 tries to turn back you dont have the leverage to stop it if your hunched over learned my lesson on that last year when i had a doe normally tame try and kill me after she got me on the ground Just my $0.02

I have 4 diffrent boxes that lead to the chute and they are 4' tall. Start with the biggest and end with the smallest and I can seperate the deer outside the boxes with no problems at all. First box can get 3-6 deer in there and the seperate as they go forward.