Dibella's Watch adds an entire new continent to Oblivion. It comes complete with a major city, castles, towns, villages, farms, monasteries and all the good stuff that makes up a Medieval landscape. There's also fighting to be had and quests to be made!
The Village of Wordham lies in the border lands between civilization and barbarism, and it's a pretty little outpost for the civilized world, although it sometimes seems it's surrounded by enemies on all sides.