Gunsan Saemangeum Marathon

The course

Full marathon, half-and-half relay, 10K and 5K. Field capped around 12,000 (roughly 4,000 each in the full / 10K / 5K), which is small by Korean major standards but enough for a real event.

Internationally certified. The city runs it, and it shows.

The course changes between years.

The seawall version uses long stretches of the Saemangeum Seawall (the world's longest, across the Yellow Sea reclamation project); the 2026 edition swapped to a Gunsan city + countryside loop with the back third on a divided highway. Both versions are flat overall with a single turnaround point and very little congestion.

The opening passes through a short tunnel: runners yell "화이팅!" into the echo and the energy is immediate.

Two warnings if you're shooting for a PR: (1) The 2026 highway stretch from km 35 to 42 looks flat on the course video but is a slight, sustained grade upward, exactly where your legs are vulnerable. (2) Coastal wind is the historical variable on the seawall version; if it's a still morning the course is genuinely fast.

Weather you should expect

Early April. Typical 7 to 17°C, start around 9°C, finish 14 to 17°C for slower runners.

Gunsan can be windy (it's coastal), but mornings are usually the calm window. Cherry blossoms are usually around peak; the 2026 edition caught them about half-bloomed in Gunsan, which is unusual since Seoul ones were earlier than normal that year.

The start area

Smaller, warmer field than the Seoul majors. The energy goes beyond the start line: Gunsan is an older city and the whole community turns out.

Halmoni and harabuji along the route, traditional musicians and modern cheer bands at the rural sections, school cheer squads in town. People genuinely show up for this race.

How to register

• Official site (saemangeummarathon.com)

  Opens in late January. Korean-first signup flow: translatable, but you'll need a Korean phone number for SMS verification.

  Critical context: Gunsan and Jeonju are the only two internationally-certified Korean marathons that do NOT require a previous certified-marathon record. That makes Gunsan the easiest "real" certified race for someone without a previous certified time, and it makes the registration window vicious.

  The 2026 site went down for 20 minutes when registration opened; the full marathon filled in 5 minutes after it came back up. Have multiple devices on standby, both partners (if doing the half-and-half) logged in, and your info pre-filled.

• MarathonGO / Marathon Online

  A parallel entry sometimes lands on Marathon Online when the main site is overwhelmed. Worth a tab.

• International runners

  There can be additional flexibility on the international side: fewer of the SMS-verification hoops, sometimes a dedicated foreign-runner allocation. The official site is the place to look.

Bib pickup

Domestic registrants: bib and race pack ship to your registered Korean address roughly 1 to 2 weeks before the race. International runners and anyone who couldn't receive a shipment: Saturday pickup at the central Gunsan pickup tent.

Race-day pickup typically available but limited; don't count on it. Passport + confirmation needed.

Getting there

KTX from Seoul to Iksan (~90 min), then a taxi or city bus from Iksan to Gunsan (~30 min) is the move. Driving is technically possible but unreliable: the race-weekend traffic compresses a normal 2.5-hour drive into 5+ hours.

Direct express bus from Seoul Express Bus Terminal is the slow but consistent alternative (~3 hours). Stay in Gunsan Saturday night.

Visitor tip

Even outside the race, Gunsan rewards a weekend.

The modern-history district (Japanese colonial architecture from 1899 to 1945) is a 15-minute walk from the central pickup tent. Good Saturday afternoon shake-out.

Eat at Iseongdang, Korea's oldest bakery, after the race. If you're running with a group, the city is small enough that everyone can stay within 10 minutes of the start.