Had a successful day finding a skateboard store and a skatepark. My local Korean friend took me to Itaewon district and we found TussaSkateboards. It's an awesome store with a friendly and knowledgeable staff that, if you want, will sell you a full set up for a reasonable price.Once we picked up a board we headed out to Dongdaemun to ride a skate park. It's been a while since I've step on a board but it felt good to ride again. There are many local Korean skaters riding around. They are all pretty good but very welcoming and fun to ride with. That park is open all day and closes at 8pm. I recommend going around 6pm because the weather is perfect and there will be a good chance of meeting some local skaters.LocationThe best way to get to Tussaskateboards is to take exit 3 out of Noksapyung Station (line #6). Then walk toward the main Itaewon street and it will be on the corner
To get to the Dongdemunskatepark. You can either walk/ride from the hostel for about 30 min. Or take the subway to Dongdaemun History and Culture Park (line #4). Once there get out at exit 12 and walk toward the National Medicare center. Which is written on the blue street signs. The park is located next to the Medical center.
This website shows the location of all the skateparks around Seoul. It's in Korean but we would be more then willing to help you find the park you want to check out.