There are a total of three Small Key's in the Castle section! Here are their locations. Enjoy, and get some treasure... Strangah.

Key #1 (Chapter 8)


The first key is located just past the room in which you meet Ada for the first time, right before facing the Cult member with the Plaga attached to him.

Map Location:




Key #2 (Chapter 9)


Your second small key is in a cupboard in the upstairs hallway, before you drop down to get the Lion Head and face the knights. Ashley will comment on Leon wearing armor.

Map Location:




Key #3 (Chapter 12):


After riding the lift at the very start of chapter 12, you come across a merchant in front of the Gondola car. The final small key is in a case right by it.

Map Location: