Jeju doesn't feel like the rest of South Korea. It is a volcanic island about 83 km off the mainland, built by eruptions that began roughly 2 million years ago, with a 1,947 m volcano in the middle and black stone walls around every field. UNESCO listed its volcanic landscape and lava tubes in 2007, and in 2016 the island's women free-divers, the haenyeo, joined the Intangible Cultural Heritage list. It also carries a heavy history, the 1948 uprising and the killings that followed, which islanders still talk about and which you'll meet on day one.
November is a good month for the island's land and a poor one for its beaches. The air is cool and clear, the tangerine orchards are loaded, the crowds are thin, and the east coast sunrise comes at a civilized 7 am. But it is not swimming season, and Hallasan, the volcano, turns into a winter climb with ice and an 11:30 am entry cutoff. This plan gives you the island as it is right now. Five days is the right length: it lets you cross the island once in each direction, climb or nearly climb the mountain, and still have a slow day.
The plan goes day by day: day one Jeju City, the old town and the market, day two the east with Seongsan and the island of Udo, day three Hallasan and the move to Seogwipo, day four the south coast waterfalls and cliffs, day five the west with tea fields, beaches and sunset in Aewol. You need a car for most of it, or a lot of patience with buses. Start on a Tuesday: the museums that close on Mondays are then behind you, and Hallasan lands on a Thursday, a weekday, when slots are less likely to be sold out than at the weekend. More on South Korea itself on the country page, and if you're also heading to the mainland, we have plans for Seoul and Busan.