How do I get the Notched Pickaxe?
You have to climb to the peak of the Throat of the World. There you will find the Notched Pickaxe sticking out of a stone.
It's found at the top of Throat of the World. You need to do the main quest to get access. At the top is the Notched Pickaxe which Fortify's Smithing by 5 points. It's rather a reference to Notch, creater of Minecraft and co-founder of Mojang, or 2 mountain climbers who got lost and people found evidence of there whereabouts by finding a mark.