Yongsan e-Sports Stadium
Yongsan e-Sports Stadium is the studio where OnGameNet broadcasts their leagues. It is located on the 9th floor of Yongsan's iPark Mall, located in Seoul. StarCraft events broadcasted at Yongsan are the OnGameNet Starleague and the Proleague.
The e-Sports Stadium also hosts a separate room, similar to a PC Bang, where offline preliminaries for the OSL and MSL, as well as the amateur Courage Tournament are held. This room is operated solely by KeSPA.
Take the subway to 용산 (Yongsan) Subway Station. The iPark Mall is almost directly connected to the subway, but there are some signs pointing the way. Enter iPark Mall and head to the elevators at the back. Go to the 9th floor and head in a North West direction for about 20 seconds until you see the iPark Mall eSports Stadium.
More directions with pictures: https://tl.net/forum/viewpost.php?post_id=2936394