There have been many different attempts to make dwarven fortresses in wurm even if it's not the same thing.
There was Uvellakish that was built on the ruins of old Bear Back Mountain that never really took off that I was a member of, Copperblazes which I hear survived for quite some time somewhere near the west coast of home, and then a time after Copperblazes fell, Onoldeler was formed by a small group of dwarf fortressers.
I was the mayor of Onoldeler for about half a year, after pretty much all of the founders dissapeared. But after a time I got bored and handed over the village to a non DF player Sgt. Scum who after deliberation decided to move the entire village to rebuild nearby Noriya and allow Onoldeler to decay. Onoldeler was located just to the southeast of the village of Greenside(Currently Crafter's Landing) and a bit north of Roadside. It had the biggest mining system I had ever seen. [ego time]Mostly mined by myself.[/ego time] We had a pretty big steelmaking operation.
I don't know of any current ones since I can't afford the premium to get my fightskill, carpentry and mining skill back and don't really feel like playing with my stats capped at 1/3rd their actual levels. You could always create one with other DF players from the board if yer really looking for an mmo with people who actually get yer DF related jokes.