The Gunsan International Marathon is on April 28th.
I registered for the 5K myself. I have a month to get ready, but I've never done much running before, so I'll just be happy if I finish in the set time and get a souvenir.
We have a wonderful manmade lake here called Eunpa (은파 means silver wave) that has a trail that's exactly ten kilometers. It even has markers along the way letting you know exactly how much distance you have left or have already covered (depending on which direction you're heading in). There's also a beautiful bridge so you can just do half of it if you're inclined. I walked the 5K version of Eunpa last night and timed myself at a normal, casual pace, just to get a feel for how doable this is for me. The time limit for the 5K is one hour, so to get a souvenir I have to finish under that. But when I walked at Eunpa yesterday I did 5K in under 55 minutes. So now I feel more confident that I can do it on the real race day, because I will be running at least some (and preferably all) of it. Hooray!