Nick and I did this last weekend, after picking up the directions from this site, which I don't know what I'd do without! We also grabbed some kimbap for the walk, and ate it on a pagoda looking out towards Dalmaji hill.
Although, we did take a few wrong turns on the way, it took us about an hour and a half to get from the metro to the beach, and the weather was the right amount of sunny and breezy to make it a lovely day.
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