This Fel Iron Ore farming guide will show you the routes that I use for farming Fel Iron Ore. There were no major changes to ores at Outland, so this guide can be used for Burning Crusade Classic (TBC) and Retail WoW.
Fel Iron Ore
Note for Retail WoW players: Don't forget to learn Outland Mining from Hanlir or Fono at Shattrath City! You can mine this ore without having Outland Mining, but you will get MUCH fewer ores!
Hellfire Peninsula is the best place to farm Fel Iron ore because there are no other types of ores in the zone. Every other zone has some Adamantite. You will get fewer Fel Iron Ore in every other zone.
The respawn time is fast enough that you don't have to go around the whole Hellfire Peninsula to farm effectively. I farmed the most ores using these two routes below.
Terokkar forest is a good alternative to Hellfire if you also want some Adamantite Ore.
Zangarmarsh is a decent alternative to Terokkar, but I got fewer ores overall. The only good thing about this farming route is that it's pretty easy to follow the route. You can watch Netflix or twitch while farming here. You don't really have to pay that much attention to where you go.
There are two caves marked with red circles on the map. You should go inside both of them and make sure that you go all the way to the end because sometimes you won't see the Mining nodes from the entrance.