Clocking in at 16 usable pages (plus a title page and advertisement at the end) 0one's Blueprints: Meteora is a fantastic, non-fantasy building for use in your fantasy campaign. I know, right?
Meteora is an honest to gosh monastery existing in our world today, high on stony peaks and looking like it would go perfectly with your fantasy campaign. Nigh unassailable, built out of stone, basements galore. In short, I'm surprised it hasn't be used in more campaigns.
Now, there's nothing stopping you. Ten Zero One offers you this traditional blue-print style map of Meteora, printable in either blue, or black and white and set up for you to slap into the fantasy (or scifi) setting of your choice. They've laid out the building quite well, leaving you plenty of room to add your own encounters and descriptions and giving any GM an instant, heavily fortified layer for your bad person, high king or godling of choice. Note that these aren't battle maps used for encounters, but literal blue-prints of the structure.
0one utilizes their Rule the Dungeon button (for Acrobat 6 or higher users) which allows you to turn on and off various features of the maps, such as grids, text, numbering and more. I've always found this useful and the blue prints for Meteora are no exception.
Coming in at under $2.00, this is a no brainer. If you need a cool, large building on a cliff face - get this. It will save you from having to design one yourself, costs less than a cup of coffee and is an actual, functioning building to boot.
[5 of 5 Stars!]