According to the comment on my last post, my brother is not actually going to teach in Jeongseon. He's in Gohan, a few valleys over from Jeongseon. Interestingly, it's the home to the only casino in South Korea that South Koreans can gamble in. It's also going to open a ski resort in December which has made him happy, no doubt. Here's a map of Gohan. I can't find a suitably close city from this list. Can you?
Go 'n' check out 37° 12' 09" N, 128° 51' 06" E - if you dare.
Hopefully he'll post something about the hamlet soon.