Participants must consult a medical institution to confirm they can run without physical strain before deciding to participate.

Participants must carefully consider their own health condition when participating in the race.

All participants must take personal responsibility to prevent injuries and safety accidents during the race.

Injuries and accidents occurring during the race are covered by the insurance company within the limits of the commercial general liability insurance, and the organizers bear no responsibility.

In mountainous areas, rapid environmental changes may occur due to bad weather (low temperatures, strong winds, rain, snow). Participants must possess the ability and be prepared to cope with these conditions for their own safety. The organizers are not responsible for accidents caused by environmental changes.

Registration using a pseudonym or borrowed name, and transferring participation rights after registration, are strictly prohibited.

If the actual participant and the insured person (the applicant) are different, no compensation can be provided for any accidents that occur during the race.

If participation under a borrowed name or the transfer of participation rights is discovered, penalties such as restrictions on future participation may apply.

All participants must install the 119 emergency reporting app when participating in the race.

100K, 50K

Assembly Time: 4:00 AM, Saturday, September 19, 2026 (Start at 5:00 AM)

Assembly Location: Yukjo Madang, Gwanghwamun Square

20K

Assembly Time: Before 7:00 AM, Saturday, September 19, 2026 (Start at 7:30 AM)
Assembly Location: Yukjo Madang, Gwanghwamun Square

*Please arrive at the starting location with plenty of time on the day of the race, drop off your belongings, and warm up sufficiently to prepare for the start.

100K

 - Physically healthy men and women aged 18 or older who have agreed to the participant guidelines

 - Participants who have acquired a UTMB Index 50K or ITRA Point 2 or higher within 2 years (June 2, 2024 ~ August 7, 2026) prior to the race registration date (Submission of certificate required)

50K

 - Physically healthy men and women aged 18 or older who have agreed to the participant guidelines

 - Participants who have acquired a UTMB Index 20K or ITRA Point 1 or higher within 2 years (June 2, 2024 ~ August 7, 2026) prior to the race registration date (Submission of certificate required)

20K

 - Physically healthy men and women who have agreed to the participant guidelines

- Cancellation is possible until 2:00 PM on Friday, August 14, 2026. After this time, cancellations and refunds are not permitted.

 * Card Cancellation: In the case of card payments, the approval will be canceled after identity verification. Depending on the credit card company, the cancellation and refund process may take 3 to 7 business days.

 * How to Cancel: You can apply for a refund through an identity verification process after contacting the secretariat (via InTheTrail inquiries).

- Continuing the race is not allowed after the cut-off time at each CP (Checkpoint).

- Participants must pass within the permitted mountain entry time; continuing the race is not allowed if the time limit is exceeded.

- Participants must practice personal hygiene management while taking part in the event.

- Participants must not damage nature or litter while proceeding with the race.

- Medical staff and medical supplies for first aid are available at each CP (Checkpoint).

- If you are injured, move directly to a first aid point (the nearest checkpoint) or contact the joint situation room. Alternatively, please ask other runners for help.

- Please be sure to assist other participants in danger.

- Personal safety highly depends on possessing mandatory equipment. Please ensure you have the mandatory equipment before participating in the race.

- Participants who receive medical assistance (excluding minor injuries) will be classified as DNF (Did Not Finish) and must follow the medical staff's decisions.

- In some mountainous sections, mobile phone calls may not be possible except for emergency calls. Participants must install the 119 app before the race and request a rescue themselves.

- Participants must strictly stay within the race course. The organizers, host institutions, race officials, and staff take absolutely no responsibility for runners participating without a bib number.

- For the convenience of participants, the secretariat operates changing rooms and a baggage storage area on the day of the event.

- Participants' belongings can be stored at the race venue, Yukjo Madang at Gwanghwamun Square.

- To retrieve your belongings after finishing, present the baggage storage sticker distributed when you deposited them. However, valuables cannot be stored, and since the contents of the stored items cannot be verified in advance, the organizers and hosts are not responsible for any loss.

- 100K participants should be careful not to mix up the drop bag stored at the intermediate CP (Checkpoint) with the belongings left at the finish line.

- Participants must declare their withdrawal (DNF) at a CP (Checkpoint). (Excluding injured persons)

- If you communicate your intention to withdraw or forfeit to the CP operating staff, your bib number will be checked, and your time measurement will be invalidated.

- CPs (Checkpoints) in the mountainous sections have good access to public transportation. Participants who withdraw or forfeit during the race should prioritize their health condition and move to the finish line, Yukjo Madang at Gwanghwamun Square, or head straight home.

- The organizers and host institutions may cancel the race, change the course (shortened operation), or suspend it in the event of an emergency.

- An emergency refers to national disasters, severe weather conditions, epidemics, or any situation deemed an emergency by the organizers and host institutions.

- If the event is canceled, the entry fee will not be refunded, and only the participant souvenirs will be provided.

- Medical support, along with beverages and food, is provided at the CPs (Checkpoints) located in the mountainous sections.

- To minimize the use of disposable items, participants must bring their own water bottles or cups in advance. Disposable cups will not be provided.

- Participants who litter personal items and trash during the race will receive a time penalty. Trash cans are available at every CP (Checkpoint).

- For safe race management, participants must finish within the time limit to have their records recognized.

- Please familiarize yourself with the time limit for each CP (Checkpoint) in advance to avoid any disadvantages during the race and after finishing.

- Participants must depart before the CP time limit for each section.

- The race course is marked with ribbons, flags, and arrows so participants can recognize the route.

- Participants must strictly proceed along the designated course; taking shortcuts or deviating from the course is prohibited.

- Participants who take shortcuts or deviate from the course may receive a time penalty or be disqualified.

- Transferring eligibility and proxy participation are not permitted once payment is complete and participation is confirmed.

- Changes in participants and proxy participation will result in disqualification, and no certificate of record will be provided.

- Furthermore, any cheating that interferes with or complicates the accurate assessment of records, such as participating with another person's timing chip, will result in the invalidation of the records for all involved participants.

※ Please note that if you fail to attach your bib number on the day of the race, or if you alter or arbitrarily change it, event staff will restrict your participation. Your record will not be recognized, which may lead to disadvantages such as restrictions on future participation.

- The secretariat collects personally identifiable information from applicants, such as real names and dates of birth.

 * Mandatory items: Personal information such as name, date of birth, participation category, address, contact number, and email is used for insurance coverage provided by the organizers and for race notifications (email, text messages). To provide better services, personal information may be shared with sponsors and partners.

Personal information will not be disclosed to others, other companies, or institutions for any other commercial purposes.

※ However, if the applicant violates the participant guidelines and terms of use, causes legal harm to others, or engages in acts that harm public morals, personal information may be disclosed to take legal action.

- The secretariat of the 2026 Seoul International Ultra Trail Running (hereinafter referred to as Seoul 100K) holds the right to disqualify participants, invite special guests, suspend or cancel the race (entry fees are non-refundable in case of cancellation due to natural disasters), and change the course.

- The race secretariat may take videos and photos of participants taking part in the 2026 Seoul 100K, and the resulting media may be posted in advertisements, social media, and on the website operated by the 2026 Seoul 100K.