Valheim's procedurally generated world is, well, enormous. The map is a massive circle, and players begin right smack dab in the middle of it. I've been playing Valheim for about 15 hours, and here's as much as I've uncovered by exploration on foot and by sea so far:
All that gray, shadowy area without detail? That's where I haven't set foot yet. So, yeah, it's quite big, and the further you go from the center the more dangerous it gets.
And as one player discovered, reaching the edge of the map is pretty damn dangerous, too. Spoilers follow, if you don't want to see what's out there until you reach it yourself.
A Valheim player named Steinfus hopped in a Viking ship and set out on troubled waters. In the video below, you can see what's at the edge of the map, and watch Steinfus try to turn their ship around to avoid it. Alas.
I guess the legends are true, sail far enough and you'll fall right off the edge of the world. On the one hand, it feels perfectly appropriate for a game that takes place in Viking purgatory. On the other hand, it's pretty damn hilarious to see the boat sucked off the edge of the world, the player's little cape flapping in the wind, before they're instakilled in a sudden explosion of loot.
But on the other other hand (yes, I have three hands for the purposes of this piece), it's tragic. Seeing the player's loot chest pop up out of the ship, I was given the brief hope it would continue floating up until it was bobbing in the ocean so Steinfus would be able to sail back out there and collect all that gear.
But then the chest plunges into the void after the ship and the corpse, presumably lost forever. That's rough. Losing all your gear is a big setback, but at least this Viking has a hell of a story to tell around the campfire.