Unless you're Korean, you'll inevitably be called a "Waygookin" or "Waygook" in Korea, which is Korean for foreigner/out-of country.
It's essentially the equivalent of the "China-towns" that we have in the west, but with a more diverse population.
It's home to a large amount of Soul's expat/immigrant community and is located directly next to one of the US army bases (which is supposedly moving out of Seoul, but they've been saying that for years). It's also home to the only mosque in Seoul. It's also one of the two bigger party neighborhoods (the other being Hongdae), so it was inevitable that as soon as bars/clubs reopened people would flock to them.
For a large part of it's recent history, it's had a bit of a seedy reputation ("Hooker Hill" is a very well know landmark) that it just seemed to be getting over the past couple years. When I first moved to Korea in 2014, I was told by multiple Koreans to "not go to Itaewon" and that "it's dangerous". Judging by the reaction's my friends who are still living over there are reporting their schools are having with this news, it may be back to square one.
Two have schools that are telling everyone if they find out you're anywhere near Itaewon, you're gone.
How Korea’s expat hub rose from seedy slum to elite escape
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