Two of the cats are interested in exploring the back on their own, one will only step outside if I go. After escorting them for awhile when training them, I gen

Two of the cats are interested in exploring the back on their own, one will only step outside if I go. After escorting them for awhile when training them, I generally let them go. I think the randomness of the long trains deters them from going far, or even to the other side, and they understand that the yard square is “home base.” There is no chance anything larger than a fox from appearing this deep in the city, and there is enough foliage to escape a stray dog if it came along. So the train is the only threatening thing, which they are (appropriately) in awe of when it passes.