Jeju Island is actually quite a large island

Hong Kong: 1,110km2, 7.3 million people
Jeju: 1,840km2, 660,000 people
If converted to the size of Hong Kong, it would be plenty of land to accommodate a population of 10 million.
I thought it was a small land because there were so few people. lol
Just as a hypothetical, if we squeezed Jeju's population into Seoul's population density, we could easily fit our entire population of 30 million. Whoa
It's insanely large land. wow
The fact that missing persons cases keep occurring means it's just that vast.