Shonan Marathon 2026

What is the course actually like?

It is a rhythm runner's dream. The route utilizes the Seisho Bypass, which means you aren't fighting vertical gain. It’s a flat, repetitive stretch that allows you to lock into a target pace without constant gear shifting. The standout feature is the scenery; you'll have Mt. Fuji on one side and the ocean on the other for significant portions of the race. However, because it’s a bypass, it can feel a bit "industrial" in sections—it’s a road race, not a park run.

What should I expect regarding the weather?

Early December in Shonan is pleasant but deceptive. You’ll likely see crisp, cool morning temperatures—perfect for a marathon—but the coastal breeze off the Pacific can add a real chill to the air, especially if you're standing around at the start line. Bring a light layer to throw on before the gun goes off, but once you hit that 10km mark, you'll be glad you don't have it on.

How are the logistics handled on race day?

The organization is efficient, but it’s a high-volume event. You’ll find water stations every 200m from the 5km mark onwards, which is generous and ensures you won't be hunting for hydration. Note that the event is pushing for sustainability, so bring your own reusable cup/bottle if you want to play along with their eco-friendly initiative. If you are running the full marathon, be aware that the time limit is 6 hours and 30 minutes—plenty of time for most, but don't dawdle.

How do I get to the start?

The Shonan area is incredibly accessible from Tokyo. You’ll likely fly into Haneda or Narita and take a train down the coast toward Oiso or Fujisawa. Most runners stay near the Oiso Prince Hotel area for easy access to the start/finish. It’s a very straightforward transit experience, making it a low-stress choice for international travelers.