Northeast of Seongsan-ri, 3.5km off the coast, is Udo Island (Cow Island), which has 1750 inhabitants yet still manages to be rural and relaxing despite throngs of tourists and tour buses, particularly at weekends. The highlights are the black-lava cliffs at Tolkani and the lighthouse that you can walk up to (15 minutes) for panoramic views of patchwork fields and brightly painted roofs. Korea’s only coral-sand beach, Hongjodan·goe Haebin, is brilliantly white. Take a picnic to the island as eating options are limited. A small community of haenyeo dives in the cove below the lighthouse.
To tour the island’s cobweb of narrow roads you have a choice of wheels, but keep in mind that the island is 17km in circumference: the tough way is by bicycle (two hours rental W5000), the soft way is on the hop-on hop-off tourist buses (W5000, every 30 minutes), and the fun way is on a scooter (per hour W15, 000) or quad bike (per hour W20, 000).