Where does “Freiburg” come from?

I need to work through this carefully, as there are some issues with the chain provided. Looking at the chain: - German frei | Old High German burg | Proto-Germanic burgz | Proto-Indo-European bʰrgʰ- | Proto-Indo-European bʰrgʰ- | Proto-Indo-European bʰerǵʰ- Problems I notice: 1. "German frei" means "free" - it doesn't lead to "Freiburg" 2. The chain seems confused - "Freiburg" is "frei" (free) + "burg" (city/fortress), so it should trace "burg" not "frei" 3. There are duplicate steps (bʰrgʰ- appears twice) 4. The progression doesn't clearly show how we get from these roots to the modern word However,

Freiburg (English): the German name