This one is Snickers^
This one is Fredrick^
Here's the "cardboard subdivision"
Here is some of the inside^ (from the right on the picture below.)
Here is another angle. As you can see it is made out of shoeboxes and scooter boxes.
Here is a picture taken ftom the top of the "T"
It even has roof access!
This is a picture taken from the bottom of the "T"
This "T" is being constsntly added on to whenever cardboard is found so the rats never get bored.