Hi Disturbed_94, welcome to the site.
I do believe you are looking to play siege maps in Stronghold 1, it will allow you to take the castle and defend it or you can siege the castle.
I think you should be able to download player made siege maps as well.
Yes I just checked and there are 794, imagine that number, maps that you can play.
Hope that helps.
Happy sieging!
[This message has been edited by Sir_Vet (edited 06-06-2014 @ 01:05 PM).]