I've been on an early 00s open world RPG kick lately (I'm not much of a gamer but every couple of years I like to binge on some niche genre or other for a few months). If I weren't already ass deep in Morrowind I'd check this out right now.
Morrowind's still better, but the Gothic series is right up there. If and when you decide to check it out, start with the first one; Gothic is a very plot-oriented series (plot as in story, not pony ass) and, while the later games are better than the earlier ones, you'll want to play them in order for the full effect.
BONUS FUN FACT: Gothic III contains the single best monster in any RPG ever - the dreaded Constipated Lizard.