Originally posted by TangoBlue:

1) Yes, raids spawn in areas you're in and built up if no work benches are nearby.

2) No. Workbenches and fires provide a "no-spawn" zone. Mobs can spawn outside that zone and attack you. If they can't get to you, they attack any unprotected buildings and farms. Place a fence or wall around your farm. That should protect it.

You haven't lived until you've had some fulings spawn inside your base at night. Ah, fun times. Found out I had a 1 meter area not covered by a workbench. Had to activate an older toon to get rid of the little snotlings.

This is partially accurate. A simple farm with no structures, or just a workbench will not generate a raid. There is a list of buildable items that will make a raid possible if 3 or more of them are in a certain proximity of one another. If you do an internet search there is a wiki

valheim raid trigger wiki