An underground gun range?
Sounds like a perfect man cave.
I want one.
Then they got the idea for longer distances. Dug a trench and put in a large diameter pipe in the backyard running horizontally - and ends up at the basement wall where they knocked a hole out. Ran a pulley system along the “roof” of the pipe to change out targets, and had lighting every so often in the roof of the pipe. Pretty clever.
Add a long arm Quilting machine and space for fabric, and it is a Perfect Quilter’s/Shooter’s Cave. I’d like to indulge both my hobbies.
I’ve several hundred round of AMMO for 3 types of guns. Locked in the Gun Safe, with enough left out for my Carry gun I can get to easy.