The Wood grows.
The Original Wood grew, but it grew too quickly, too large. It could not hold all of its creatures. So, the magic that created the Wood created the Split Path.
Yet still, it was not enough. New creatures arrived daily, and the Wood could not contain them all. Thus, the Great Shift took place.
It happened over three days. As the first day dawned, the Wood drew a new border, and pushed cliffs and water ways out towards it, to make barriers to the outside world. Then over the next two days, areas shifted and were cut off from each other. A new castle was created, where the humans and other castle-dwellers took refuge.
But not all had gone smoothly. Families and herds were separated by the shift, as it split lands and the Wood changed.
Now, however, the Wood is fixed. It can easily grow to contain more creatures, but the magic does not shift the lands around as it did before. If the meadows are located near the castle today, they will be located there tomorrow, which means that those that live here will not have to worry about getting lost any longer.