Gangwon is the mountainous province on Korea's east side, facing the East Sea. Korea Trip Map currently covers one place here: Gangneung. It is a coastal city with a long beach, pine forests, a famous coffee street, soft-tofu restaurants and well-preserved historic buildings, and it is easy to reach from Seoul by fast train in about two hours. Other Gangwon towns and the national parks nearby are not yet on this site, so this page describes Gangneung alone.
Gangneung works well as a slow two-day trip. Spend one day on the coast, walking the beach, trying coffee at the seaside cafes and eating fresh seafood, and the other day on the historic side of town, with its scholar houses and old gardens. Sunrise over the East Sea is a classic reason to stay overnight, and the winter air is crisp and clear, though cold and windy on the shore.
Plan around the season. Summer brings crowds and warm water on the beaches, autumn has clear skies and mountain color, and winter is cold, with snow in the nearby mountains. Weather on the coast can shift quickly, and some beachside businesses reduce hours outside the summer season. Check opening times and the train timetable before you go, as both change.