No BASE in Korea
If there's any BASE jumping in Korea, it's a well kept secret. 
So this isn't technically naming a site. I passed this odd tower on the way to Seoul the other day. It's at the ThyssenKrupp-Dongyang elevator factory. Their test tower is 157m/510ft tall. http://www.thyssenkrupp-dongyang.co.kr/index_eng.asp
You can find the specs under the "Profile" link. Pretty unique looking.