World of Warcraft: This and That

Mining 176-230 - Mithril and Truesilver

Horde and Alliance

You could still be smelting for this part and skipping the first half of this mining leveling guide, but it will start to cost a lot more gold and you may want to read this gold guide if you decide to smelt.. Don't forget to go back to the mining trainer at 225 so you can advance your leveling skill.

The Hinterlands

I've personally never done this route but I hear it is good. I spent most of my time in Tanaris when I leveled mining to 230 following the mining maps in this leveling guide.

Badlands

You probably want to spend most of your time in the eastern loop or in the cave in the south west. It's not bad to alternate between the two spots but the eastern loop and southwestern cave are where you will level mining the fastest.

Tanaris

This is where I spent most of my time riding around in circles while leveling up mining. I always equipped my enchanted riding gloves, my mithril spur boots, and my carrot to increase mount speed because this is a long run. Also, if you drop down into some of the cave areas around the Noxious Lair you'll find the leveling is good there too; it's a lot less competitive and you are almost guaranteed to have all to yourself.

Mining 231-275 - Thorium

Horde and Alliance

If you plan on smelting or would like to smelt but need some more gold take a look at thisguide.

UnGoro Crater

Ungoro Crater, one of the most highly competitive zones known to the game(or used to be). Good luck here! Don't forget to drop down in the Slithering Scar for some extra leveling.

Winterspring

This is one of the best zones for Thorium. There north cave thats marked on the map is a full cave system that you can go in to, the bottom cave is just very small caves but thorium spawns in that area. The very bottom area in green is full of level 60ish Elite mobs and nothing but it. There's thorium veins down there but if you aren't a higher level you might have a tough time getting to them.

Silithus

Silithus is another good zone to farm Thorium Ore in. The areas marked in orange are hive areas, there are complex tunnel systems in each area that you can follow down to get Thorium. If you don't want to drop into the tunnel systems there is still a decent amount of thorium if you just perform the circuit indicated on the map.

Mining 276-325 - Fel Iron

Horde and Alliance

Hellfire Peninsula

The easiest leveling route to farm some Fel Iron is to stay in Hellfire Peninsula. Fel Iron prices may have gone up on your server due to decreased supply so you might want to learn how to use mining to make gold with this guide. You can just loop around the Orcs near the citadel but if you follow the entire leveling route around the mining map it will also be beneficial. Watch out for the elite area in the northwest area and there are some other crowded areas like the Pools of Agonnar that can be a headache while leveling. Remember Fel Iron can be skilled up all the way to 375+ if you wish and you can skip the other sections of this leveling guide.