Castle Book I is a 1978 fantasy role-playing game supplement published by Judges Guild.

"[2]: 191–192  A listing of cumulative sales from 1981 shows that Castle Book I sold over 15,000 units.

"[1] Patrick Amory reviewed Castles Book I for Different Worlds magazine and stated that "Some are a little outlandish, but who cares?

Again, its usefulness lies in the fact that the GM will almost certainly not have all the castles in his campaign mapped out in this detail.

"[4] In the May 1988 edition of Dragon (Issue #133), Ken Rolston said, "There are no details for the functions or contents of the individual buildings, but it’s nice to have the layouts when whipping up an adventure setting on short notice.