Discovering Jeju City will be a piece of cake once you’ve organized a rental car. But before you land in a new and unfamiliar place, it’s always a great idea to know a little basic info about the area.It sits 280 miles to the south of Seoul, the buzzing national capital.Facts and figures intrigue you? Want to know how many people live in this part of Jeju before you venture off on your day trip? At the last count, the population was 408,400.