Games with huge explorable worlds

Hi all! I would like you to recommend single-player games that have huge explorable worlds. To make the list smaller, I need to mention the "usual suspects" (mainly the GTA games), also their clones: Mafia 1,2, The Godfather 1,2, Gun, Just Cause games, Mercenaries, etc.

The Gothic, Risen, Two Worlds and The Elder Scrolls games have some big worlds also.

If the game is lesser known, it's even better. If the worlds are as huge as they can get, it's also better. I'm looking for the worlds the size of the EVE:Online world or World of Warcraft BUT it should be single-player AND for the PC. If the world is not that big, it should be no problem, but I encourage you to write the best matches you can think of.

I suggest Dragon's Dogma: Dark Arisen edition. It's amazing and unfortunately underrated. The world is huge and varied with amazing monsters and random events. There is a fast travel system that is very limited and won't be available until later in the game, which will force you to "walk" a lot. Some hated that but some loved it since it is very useful for grinding and exploring. Also the game has one of the best " Night Time" systems in any open-world game. You won't be seeing anything without a lantern and there will be different enemies who only spawn at night. The entire game world will dramatically change near the end of the game which will make you want to explore it all over again. The game starts slow but you should know that since you like these type of games.

Minecraft, Terraria also Saints Row 3 & 4

Fallout 3, Fallout NV, and Two Worlds 2 is what I am going to start with.

I assume you don't mind genres, as you mentioned both modern action games and fantasy RPGs...

Fallout 3 GOTY
Fallout New Vegas (Ultimate Edition)
Divine Divinity
Sacred (Gold Edition)
Sacred 2
Dungeon Siege + Legends Of Aranna
The Saboteur
Neverwinter Nights (Diamond Edition)
Kingdoms Of Amalur: Reckoning
Far Cry 2 & 3
Batman: Arkham City
Saints Row 2, 3 and 4

Those are the games that immediately come to mind.

New Vegas' world is microscopic. Don't get me wrong, I love that game -particularly with mods- but that is definitely not something that falls under "huge world."

I second Saboteur (#1 most underrated game in the last five years) and Amalur.

Thanks for the recommendations!

By the way, I don't want to sound like a smart@ss here, but why didn't anyone mention Ultima games? I read somewhere that it had an even bigger world than Morrowind or Skyrim but can't confirm it as I haven't played it (yet). Are there even old-school gamers here lurking in the depths of this site?

Also, when I wrote "If the game is lesser known, it's even better." I really meant it.

dayz

If I'm on the ground and minimizing my fast travel, Far Cry 3 is plenty big with the two islands and the waters in between.

I actually did a "fast walk" on the first island from west to east. It took 30 minutes non-stop.