Leave from Portland at 7:30am and get into San Fran at 9:30am
Leave from San Fran at 1:15pm and get into Incheon at 5:30ish pm...the next day! ...thanks to that pesky little international date line (+12 hrs). Either way that's a really freaking long flight!
Take a bus from Icheon to Gimpo airport...and pray like hell we get on the right bus. Although now that I have my handy "I'm an American idiot, need to go to the Gimpo airport, please don't rob me," translation I have no fear of arriving with plenty of time to spare...lol. Ok the card doesn't really say that...although I think it could easily be implied.
Leave from Gimpo airport at 8:10pm and get into Gwangju at 9:25pm
So to recap I'll leave at 7:30am on Sunday and finally arrive in Gwangju at 9:25 pm on Monday. Traveling to Korea sux!

Now you know where the international date line is :)