Only the dungeons in Daggerfall and side quests were random. Everything else is static. I've beat Daggerfall at least 10 over the years. That's the randomness that I've found.
The entire world was randomly generated using a computer, though. They didn't hand-place their assets. That would have taken decades to make.
Actually it wasn't. Towns were in the same location no matter how many times you restarted the game. New characters that I started always made Burgwall their home town. It has all four guilds and a few temples near it. It's also really close to Daggerfall - walking distance close. Witch coves were always at the same locations from game to game as well. --- I have Medulloblastoma and no Cerebellum. Sorry if my post doesn't make any sense or I miss use words.
Daggerfall. I don't think there's a person on the planet who visited every town in Daggerfall. Especially not by walking.
Also, the world of Daggerfall was not randomly generated. The towns and cities were always the same, and in the same locations. The landscape in between towns (trees, rocks, etc.) was random, but to me it still counts.
In modern games probably MMOs. Just Cause 2 was also enormous. --- Run you pigeons, it's Robert Frost!
Just Cause 2 was the biggest i played. The fact that you could fly Jets/boats/cars/etc really helped give it a large feel. You'll be going real fast in your your jet, thinking how slow your car is, and then you realize it's still going to take you 10 minutes by jet to get to your destination
i beat the game, and my completion was around 40% (25 hours of play) --- nyuuuuuuuuu~