Near the Municipal Stadium in central Sokcho, the wall was deserted and seemingly neglected when we visited. That said, if you maybe brought a wrench for some twirly-holds, the wall would suffice.
The wall is about 16 meters, but so overhanging at points the longest routes are 18 meters.
I suppose with Seorak at it's doorstep, people in Sokcho don't hang out at an artificial wall much.
It's in the Municipal Stadium/Gym complex. Straight and right.
This is right near the tourist info center on 관광로 (Tourism Street). If you're coming in from the tunnel (Misiryeong-ro) on 56, it's a major turnoff right to get to Seoraksan.
I really can't imagine many reasons you'd go to this wall if you're going to Seoraksan, though!
It's in the middle of Sokcho. Water and snacks nearby.