Oh yes, everything was done outside. I worked 30 years as a small engine mechanic. Seen my share of mouse nests in lawn motor engine cooling shrouds. Amazing where those little buggers will build a nest at! One has to remember, when this was put away in the barn, it was nothing but a toy that was nolonger being played with. I am sure it was forgotten about for many years. They were cleaning out the barn and getting ready to move to a condo I believe if I remember what he told me. When they found the train set, he remembered the autistic guy in the Jeep club that loved trains. Hence how I ended up with the set. They just wanted it to go to a good home. They thought I could fix it up and make a few bucks off it. I was like heck no!, gonna fix it up and enjoy it!! AD