I used Mythras Dark realism for the castle, download it here www.planetminecraft.com/texture_pack/16x-18-dark-realism-v08/

Not completely done, if you spawn in a different place,(When i get the download url.) turn creative and normal render distance and go straight ahead, you'll find it. :)

Diamond if you like.

Additional Notes

The rules at the beginning are for my LAN server, don't mind them.Also, if u ever use this for a server or whatever, give me credit.

UPDATE-Just added rail, it give a round tour of the castle!