A computer strategy game from Firefly Studios, released by Take2 and GodGames. Published in late 2001.
Stronghold is a Castle Sim, set in the medieval (of course) Britain. It was made by the people who made Caesar games and Lords of the Realm games.
Basically, it simulates the building, defending and conquering castles - from building, economic and military perspectives. It has various types of play; a full campaign (start from scraps, and follow the development of the castle technology while you are at it) with battles and all, an economic campaign where there are no battles but more than enough trouble keeping the pennies in row, individual battles, historical castles to attack and defend, multi-player game (via GameSpy), and last but not least, a free building mode!
Sounds like great fun for RTS and simulator/manager game crowd, right?
I haven't played it much yet, but it seems like a pretty nice mix of real-time strategy, SimCity-style building, and a bunch of base-building things not often found in Age of Empires II. =) The only thing I really didn't like was that in the beginning of the military campaign, the missions were mostly about killing wolves and stuff. (Maybe they added that there just for shocks to explain why there are no wolves in Britain these days! =)
Not to be confused with a computer strategy game called Dungeons & Dragons: Stronghold, a game published in 1993, generally considered to be not that great, but I haven't seen it so I won't review it either.