Beyond the narrow canyon's entrance, you can find a Site of Elden Ring Runes Grace at the Scavenger's Shack. Here it is where you will meet Character Roderika. They'll give you a few bits of information about the castle along with it's Spirit Jellyfish Ashes to hold to, and eventually proceed toward the Roundtable Holder.
A little further on the road are more patrols of soldiers and soldiers that will eventually lead you to the main Stormveil Castle Gate, but the gate is heavily fortified with rows of barricades lined by soldiers, and an army of ballistas at the entrance of the tunnel. It's a formidable range and strength, so it is recommended to accelerate on Torrent into the thick forest that lie to the left as arrive, then speed ahead along the castle walls to ambush and eliminate the ballista. You can then take out the other army in smaller teams.
After entering the tunnel, you will find one final Site of Grace before you must battle the boss that guards the entrance to Stormveil Castle proper - Margit the Fell Omen.
Margit The Fell Omen Boss Fight Guide.Margit the Fell Omen is an interesting aptitude test in Elden Ring, as he's way more imposing and fearsome as any miniature boss that you've likely fought in the smaller dungeons of West Limgrave. If you've been avoiding these areas or fought straight in this area, it's possible for him difficult to overcome. it's highly recommended that you learn to Elden Ring Items for sale master the art of combat by clearing the smaller dungeons within West Limgrave before attempting this fight.