This is the Witches castle with a bunch of animals turned to stone that the witch would do with her wand and leave them there as a trophy almost. Later on in the book it is where Aslan goes and breathes on the animals and they come alive again and join them in battle. To defeat the witch and take over Narnia again.
This is the last battle in the last battle Peter Susan and Edmund all fought while Lucy healed the injured animals fighting for their side. The witch was fighting with a knife instead of her wand. Peter was using a sword Susan was using a bow and Edmund was also using a knife. Aslan was mostly fighting the witch because hey were the most strongest ones and then eventually Aslan's army won the the battle and took back Narnia.