Korea is a land of mountains, but compared with the famous peaks in other parts of the world, Korean mountains are really just "hills". Nearly every one is climbable in a day; there are very few multi-day mountain hikes available. But that isn't to say the views aren't fantastic from any of them.
The best thing is that it doesn't even take a mountain to get a fantastic view. Just 8 1/2 minutes is all that's needed to climb Nojeok Hill and see the entire Ansan area.
So, for the record, here's the climb from bottom to top... (BTW, sorry for the shaky camera... and the smoggy view at the top... Other photos on this weblog were taken on clearer days.)