The Old Palace is a place that was built by the moles who survived the fall down the pit in the dungeon that became the Chamber of Candles. It is deep under ground and was used as a nursery by Captain Padra and Captain Crispin. There are many way to get into it.
Lugg, Arran, Captain Padra and Captain Crispin are using the Old Palace as a secret nursery for the baby animals who were named for the cull. Moth the mole maid and Mother Huggen take care of all the babies. When Tay is searching for the palace with a few moles, everybody gets out in time with the leader Arran.
Tay is later tied up underneath a boat during the Spring Festival. Under the same boat is Mother Huggen, Moth, and all the baby animals.
The Old Palace is used again as a nursery for the young animals to stay away from the Fouldrought disease.
The Old Palace is used as a hiding place from the ravens. All the young animals hide there while the ravens are attacking. They are later moved to other Burrows.