Geoje City's official bus information site lists Gohyeon Intercity Bus Terminal as a major hub and provides terminal contacts and route information. It lists connections with cities including Seoul, Daejeon, Busan Sasang and Jinju.
Jangseungpo and Gohyeon are separate intercity boarding points. The city's page lists the normal travel time between Jangseungpo and Gohyeon as about 30 minutes under normal conditions.
The local bus network is a separate stage from the intercity ticket. The official route table shows, for example, Route 10 linking Gohyeon through Suwol, Okpo and Jangseungpo toward Neungpo, with related variants. Southern beaches and villages use other local route families, some from hubs such as Jeogu.
Practical plan: confirm whether your long-distance ticket ends at Gohyeon or Jangseungpo; search the exact beach, port or accommodation stop in Geoje's official system; check the return bus before going deep into the southern or coastal area; and leave extra time when connecting to a ferry or timed activity.
Gohyeon Intercity Bus Terminal: 1688-5003. Jangseungpo intercity stop: 1688-0078.