This game and its sequels are really quite special games - more than just the Ultima clones that they might appear at first glance.
They had some very interesting game mechanics for the time, such as splitting your party and sending some of them off to do certain quests or errands - which, in the days of the Commodore 64 (the system I played the game on) were pretty novel for the time.
I still have reams of printed out (DOT Matrix even!) NPC conversations back at my parents house and drawings I made of the different dungeons and player characters I made when I wasn't playing but couldn't stop thinking about the games.
This and the non-traditional final boss battle really made this one stand out. The sequels were great too, and these games are quite lengthy.
Also - a neat memory I have from the first game: Remember the warranty/registration cards that used to come with video games that nobody ever filled out? Well, I filled one out for this game for some reason and sent it in.
A few months later IIRC, I got a sturdy envelope from Mindcraft Software that had a floppy disk inside, containing a patch/update to the game. Imagine that, pre-internet and a company just mails you a patch update to the game you are playing. Didn't even know it needed one, as there were no websites, nor magazines that I had access to anyways. I thought that was pretty darn cool.
Awesome, epic RPG series.