In God of War Ragnarok, Jarnsmida Pitmines in Svartalfheim is probably the most laborious region to return to after you’ve completed the story and are on the hunt for collectibles. You can’t get to it from The Forge like you did during the story. Instead, you have to approach from the south, and come via Sverd Sands and The Applecore.
Related: How to get to Niflheim in God of War Ragnarok
How to return to the Jarnsmida Pitmines in Svartalfheim
Starting at the Aurvangar Wetlands Mystic Gateway, use the ferry to get to Sverd Sands, then use the lift to get from Sverd Sands to the southern end of The Applecore, where you’ll find the Applecore Descent Mystic Gateway. From here you have a long, fairly linear trek through the mine tunnels, heading north until you reach the spiral section of the mine.
Drop off the spiral onto the bridge on the northwest side, then head northwest across that bridge. Turn left and throw a weapon at the explosive pot behind the ore to blow it up (you might already have done this during the story), then jump across the gap that the ore was blocking. Swing across to the northwest, then climb up, and go through the large door. Use your Draupnir Spear to swing across to the north, and you’ve reached The Applecore Mystic Gateway. Go through the gate (not the Gateway), then drop down and crawl through the gap on the left. Climb up to the west, then follow the tracks up until you emerge into the Jarnsmida Pitmines.
When you emerge from the tunnel, follow the tracks left, then drop to the left. Go to the end of the platform, then throw a Draupnir Spear into the hole below you and to the left. Now drop down again and use that spear to swing across. Now interact with the rope to create a massive zipline leading northeast, and use that zipline to reach the Jarnsmida Pitmines Mystic Gateway, which is concealed beneath some brambles.
