It's taken almost five months, but within a day or two, I'll be completely finished with my coops/run, and I'm still alive (bankrupt but alive). Since about three days ago, I finally finished the run's outside perimeter with a truckload of dirt and another load of sand. Any interested predator will have to dig. When he starts digging, after going down four inches he will run into a 2x4 fence wire. If he wants to get under that, he'll have to turn around and go back thee feet before he can start digging under the wire. IF he figures out how to do THAT, once he gets up to the wall he will run into a buried 2x6 board, then below the board there's are eight inches of 1/2-inch hardware cloth buried in a trench, i.e., he'll have to go 14 inches straight down . If he does do that, once he starts up those 14 inches inside the run, after digging through dirt, he'll reach the level that has one foot of SAND that covers the entire floor of the run; the sand will run down into dirt hole he dug through, and it, hopefully, will fill his hole entrapping/killing him before he can reach the surface of the sand. The run is not connected directly to the two coops. The chickens have to go through a two-foot tunnel to reach the pop doors in order to enter the coops. Before a predator can lift the pop door from inside the tunnel, he'll first have to go back OUTSIDE the run to unlatch the pop door so that it can be raised or lowered, then dig his way into the run again so he can lift the pop door to enter the coops. Any predator that can do all that deserves a meal of chicken and is welcome to it. BTW, all doors and gates have locks. All the locks use the same keys. We keep a key right by the outside nest/egg doors and the gates for our own convenience. If a predator can figure out how to put the key into the lock, open/remove the lock, and then undo another latch above, once again, that predator deserves a chicken and is welcome to it. EDIT: The run is eight-feet tall and is covered sides and ceiling with 100% 1/2-inch hardware cloth.