The Big Fir Tree serves as the setting for the very beginning and the very end of The Tale of Peter Rabbit.  It also serves as the setting in the beginning and in the very end of The Tale of Benjamin Bunny. It is the home of Mrs. Rabbit, Peter Rabbit, Flopsy, Mopsy, and Cottontail. Specifically, the Rabbit family lives in the sandbank underneath the Big Fir Tree. Presumably, it was also the home of Mr. Rabbit.