To farm a lot of Elden Ring runes, you have to get to Elden Ring Items this area, the Dynasty Mausoleum Entrance, which is in Siofra River, how do you get there?

1. Get the Pureblood Knight's Medal

Once you start the game, you’ll come to the place called The First Step, progress forward do what you got to do and you'll end up coming to Stormveil Castle, you need to beat the boss Margit the Fell Omen, once you do that, you can come back down to The First Step and just to the left of it, there will be an NPC, if you speak to this NPC and follow his quest line, you'll eventually get the Elden Ring item called the Pureblood Knight's Medal.

If you messed up the questline, the guy is called the White-Faced Varre, which you find at The First Step, the only other way to actually get down to this great rune farming spot is to basically progress through the entire game or almost the entire game and actually come to this area, you need to progress past the capital up into the Mountaintops of the Giants, you need to beat the boss Commander Niall, he'll give you the first half of the Haligtree Medallion, which is found in Village of the Albunarics, the other half comes from the NPC back down, then you take that Medallion to the Grand Lift of Rold, you press the left over on your d-pad, you'll come up to elden ring items buy this area, and there will be a teleporter, which will take you down to this area, but that is extremely long, just doing a White-Faced Varre quest line, if that option is still there for you, it gives you the Pureblood Knight's Medal.