
Runners Guide
Ultra Trail
Regulations and general information

Categories / Age groups / Assessment
Strecke | Altersklasse | SINGLE | Team DUO |
---|---|---|---|
O-SEE 100k | from 18 years of age | 1st - 6th place M/F Overall | 1st place M/F/Mix |
O-SEE 75k | from 18 years of age | 1st - 6th place M/F Overall | 1st place M/F/Mix |
O-SEE 50k | from 18 years of age | 1st - 6th place M/F Overall | 1st place M/F/Mix |
O-SEE 25k | from 16 years of age | 1st - 6th place M/F Overall | 1st place M/F/Mix |
O-SEE 16k | from 16 years of age | 1st - 6th place M/F Overall | - |
Light 6,6k | from 16 years of age - Masters | 1st place M/F in every age group | - |
Juniors 4k | Under 14s/16s | 1st - 3rd place M/F in every age group | - |
Youngsters 1,3k | Under 10s/12s | 1st - 3rd place M/F in every age group | - |
Minis 500m | Under 6s/8s | 1st - 3rd place M/F in every age group | - |
Walking 6,6k | every age group | - | - |
Team DUO
Misery always loves company, so why not suffer the endurance challenge with a friend (Men, Women or Mix) rather than solo. DUO teams must start and finish at the same time to be eligible. No individual scoring possible.
Registration criteria for O-SEE 100k
Qualifying for the O-SEE 100k requires at least one successful trail race of no less than 75 kilometers completed within the advertised cut-off time within the last 5 years. The race must be specified during registration.
Distances
Strecke | Distanz | Höhenmeter | XTERRA | ITRA | UTMB | Läufer-Cup |
---|---|---|---|---|---|---|
O-SEE 100k | 100,7 km circuit | 3.654 m+ | ||||
O-SEE 75k | 75.3 km circuit | 2.806 m+ | ||||
O-SEE 50k | 50.9 km circuit | 2.340 m+ | ||||
O-SEE 25k | 25.4 km circuit | 1.150 m+ | ||||
O-SEE 16k | 16.9 km circuit | 586 m+ | ||||
Light 6,6k | circuit - short section on asphalt and natural forest paths | |||||
Juniors 4k | circuit - short section on asphalt and natural forest paths | |||||
Youngsters 1,3k | circuit - short section on asphalt and natural forest paths | |||||
Minis 500m | circuit - Kurpark Oybin | |||||
Walking 6,6k | circuit - short section on asphalt and natural forest paths |
Detailed course information and GPS tracks available at www.o-see-ultratrail.de.
The O-SEE 50k and O-SEE 25k courses are part of the global XTERRA Trail Run World Series, and each will be counted as a qualifier for the XTERRA Trail Run World Championship. Slots will be given to the top finishing individual runners and teams DUO.
All O-SEE Trail Runs are considered as classification races for the UTMB® Index (100K, 50K and 20K, respectively).
The O-SEE 100k, O-SEE 75k, O-SEE 50k and O-SEE 25k courses have been evaluated and are listed by the ITRA with 4, 3, 2 and 1 points, respectively, as well as being represented in the ITRA National League.
The courses Minis 500m to O-SEE 16k will be counted as runs in the SachsenEnergie Läufer-Cup series.
Start fee
Strecke | First Mover | Early Bird | Forward Thinker | On Time | Last Minute |
---|---|---|---|---|---|
until 31st JAN 2025 | 1st FEB until 30th APR 2025 | 1st MAY until 31st JUL 2025 | 1st AUG until 8th OCT 2025 | on site | |
O-SEE 100k | € 110,00 | € 120,00 | € 130,00 | € 140,00 | € 150,00 |
O-SEE 100k Team DUO | € 190,00 | € 210,00 | € 230,00 | € 250,00 | € 270,00 |
O-SEE 75k | € 80,00 | € 90,00 | € 100,00 | € 110,00 | € 120,00 |
O-SEE 75k Team DUO | € 130,00 | € 150,00 | € 170,00 | € 190,00 | € 210,00 |
O-SEE 50k | € 55,00 | € 65,00 | € 70,00 | € 75,00 | € 85,00 |
O-SEE 50k Team DUO | € 90,00 | € 110,00 | € 120,00 | € 130,00 | € 150,00 |
O-SEE 25k | € 35,00 | € 45,00 | € 50,00 | € 55,00 | € 65,00 |
O-SEE 25k Team DUO | € 50,00 | € 70,00 | € 80,00 | € 90,00 | € 110,00 |
O-SEE 16k | € 25,00 | € 35,00 | € 40,00 | € 45,00 | € 55,00 |
Light 6,6k | € 15,00 | € 15,00 | € 15,00 | € 15,00 | € 25,00 |
Juniors 4k | € 8,00 | € 8,00 | € 8,00 | € 8,00 | € 18,00 |
Youngsters 1,3k | € 6,00 | € 6,00 | € 6,00 | € 6,00 | € 16,00 |
Minis 500m | € 5,00 | € 5,00 | € 5,00 | € 5,00 | € 15,00 |
Walking 6,6k | € 15,00 | € 15,00 | € 15,00 | € 15,00 | € 25,00 |
The payment of the entry fees takes place directly during the online registration. The organisers have commissioned the company Baer-Service GmbH to handle the payment transactions. On the day of the competition, the entry fee can be paid in cash or by card and mobile payment services on site.
Time limit / Withdrawal & Cut off
Strecke | Zeitlimit | Zielschluss | Cut off | Switch |
---|---|---|---|---|
O-SEE 100k | 20 h | 12:00 pm | K45: Hochwald/Pod Hvozdem (50.8223 N, 14.7229 E) - 1:00 pm K50: Mařenice/Antonínovo údolí (50.8073 N, 14.6663 E) - 2:00 pm K84: Brandsteinweg/Wiesenweg (50.8319 N, 14.7419 E) - 8:45 pm | - O-SEE 75k O-SEE 75k |
O-SEE 75k | 15 h | 9:00 pm | K45: Hochwald/Pod Hvozdem (50.822337 N, 14.722908 E) - 3:00 pm | O-SEE 50k |
O-SEE 50k | 10 h | 6:00 pm | K43: Stern Jonsdorf (50.838489 N, 14.715849 E) - 4:00 pm | - |
O-SEE 25k | 7,5 h | 6:00 pm | K18: Stern Jonsdorf (50.838489 N, 14.715849 E) - 4:00 pm | - |
O-SEE 16k | 6 h | 6:00 pm | - | - |
Switch
Participants of the O-SEE 100k and the O-SEE 75k can change to the shorter distance during the running competition. This switch is possible with timing and scoring. The organisation office must always be informed of this by telephone or at the latest by announcing it at the course switch point. Participants of the O-SEE 100k who reach the cut off point “K84 Brandsteinweg/Wiesenweg" after 8:45 p.m. must run directly towards the finish.
Switch points:
-
O-SEE 100k ➘ 75k: Mařenice/Antonínovo údolí (50.807339 N, 14.666308 E) = K50
-
O-SEE 100k ➘ 75k: Brandsteinweg/Wiesenweg (50.831850 N, 14.741903 E) = K84 … (total distance 85 kilometers)
-
O-SEE 75k ➘ 50k: Hochwald/Pod Hvozdem (50.822337 N, 14.722908 E) = K45
Withdrawal
In the event of the race being abandoned at a refreshment point, the start number (and GPS tracker) must be handed in or, in the event of a "wild" exit on the course, the organisation office must be informed immediately by telephone. A contact telephone number can be found on the race number. In the event of failure to do so, any search and rescue costs incurred may be charged to the participant.
In the event of abandonment, there is no entitlement to return transport, even if this is attempted within the scope of possibilities.
In case of an acute health emergency, please dial the emergency number 112 immediately.
XTERRA O-SEE Ultra Trail 50k & 25k
XTERRA Trail Run World Series
Compete individually, regionally or globally in the XTERRA Trail Run rankings, or push to the front of the pack in your age group to qualify for a place on the starting line at the annual and invite-only XTERRA Trail Run World Championship.
See the XTERRA Trail Run World Series page for information regarding the rankings, qualification rules and criteria.
Distances & categories
The XTERRA O-SEE Ultra Trail includes both half-marathon (O-SEE 25k) and full-marathon (O-SEE 50k) races, with individual and team DUO categories available.
Deferral with O-SEE Flex / Change of distance / Registration transfer
The registration is binding for the participant. The registration fee will not be refunded for any reason.
Deferral Trail Runs (O-SEE Flex)
O-SEE Flex offers the possibility of moving your starting place to the following year’s event free of charge and without giving any reasons until the official registration deadline. This option can only be booked with online registration. The fee is a flat rate of € 20.00 per participant in addition to the entry fee.
The race entry can be deferred to the following year by issuing a voucher worth the amount of the entry fee paid. The prerequisite for sending the voucher code is successful deregistration via the link in the registration confirmation.
Without O-SEE Flex, deferring your starting place is not possible!
Changing to a different distance / Registration transfer to another person
It is possible to change the race by transferring the registration already made to a different distance. In this case, any surcharge on the registration fee must be paid if upgrading distances. Differences in entry fees will not be reimbursed.
Athletes who have already registered but are unable to take part in the race have the opportunity to transfer their registration to another athlete.
In the event of changing the race category or participant, please contact Baer-Service GmbH:
Email: info@baer-service.de
Phone: +49 (0)351 40220900
Service
The organisation fee includes the following services:
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O-SEE starter bag with giveaway
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Finisher medal for all participants
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Prizes for 1st - 6th place finishers M/F of each course (Trail Runs), for the first team DUO M/F/Mix (100k, 75k, 50k and 25k), for the first-placed M/F under 18s to Masters or 3 first-placed M/F under 6s to under 16s (Light and Kids Runs).
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Printing of certificates directly at the finish line upon personal request and online for downloading
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Electronic time recording with transponder system
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Live GPS tracking for the 100k, 75k, 50k and 25k courses
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Catering in the finish area and on the courses
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Carb loading and pasta dinner on Friday, 17th October 2025, 5:00 pm to 8:00 pm (reservation with online registration)
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Changing and shower facilities
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Luggage storage in the start/finish area
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Individual runner photos by Sportograf (photos can be purchased after the event)
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Comprehensive medical care along the course by the DRK and the Zittau Mountains mountain rescue service as well as a senior accident doctor
Competition briefing in the start and finish area
Friday 17th October 2025, 5:30 pm
Briefing for all distances // Competition area
Saturday 18th October 2025, 3:45 am
Short briefing for O-SEE 100k // Competition area
Saturday 18th October 2025, 5:30 am
Short briefing for O-SEE 75k // Competition area
Saturday 18th October 2025, 7:30 am
Short briefing for O-SEE 50k // Competition area
Saturday 18th October 2025, 10:00 am
Short briefing for O-SEE 25k // Competition area
Saturday 18th October 2025, 11:30 am
Short briefing for O-SEE 16k // Competition area
Participation in one of the competition meetings is obligatory for every starter!
Start times // 18th October 2025
O-SEE 100k: 4:00 am
O-SEE 75k: 6:00 am
O-SEE 50k: 8:00 am
O-SEE 25k: 10:30 am
O-SEE 16k: 12:00 am
Light 6,6k / Walking 6,6k: 11:45 am
Juniors 4k: 11:00 am
Youngsters 1,3k: 11:05 am
Minis 500m: 11:30 am
The starting times may still change slightly! Please refer to the up to date information and the schedule on the website!
Checkpoints Trail Runs
Checks at hidden checkpoints may be carried out along the trails.
Route markings
The routes are marked. However, markings may be missing or changed by rain, wind, vandalism or order-loving fellow citizens. It is recommended that all trail run participants carry a GPX-enabled phone or navigation watch with the track/route data of the respective route stored. The participant should be able to find the route even in the absence of markers.
Disqualification
Anyone who leaves the running course, does not follow the regulations, does not pass a control post, behaves in an unsportsmanlike manner or abuses doping will be disqualified.
Registration
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Online: www.baer-service.de
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Registration: from 13th January 2025
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Registration close: 8th October 2025, midnight
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Participants limits: O-SEE 100k – 100 participants // O-SEE 75k – 150 participants // O-SEE 50k – 200 participants // O-SEE 25k – 300 participants // O-SEE 16k – 250 participants
After your registration, you will receive your personal registration confirmation by email. This entitles you to pick up your starting documents at the starting documents desk. You can only pick up your race documents without a registration confirmation upon presentation of your identity card.
Underage participants require the written consent of both legal representatives to start. This must be presented when collecting the starting documents.
Issue of starting documents / late registration
Friday 17th October 2025, 2:00 pm to 8:00 pm
Issue of starting documents and late entries // Start and finish area in the Kurpark, 02797 Oybin
Saturday 18th October 2025, 6:00 am
Issue of starting documents and late entries // Start and finish area in the Kurpark, 02797 Oybin
Participants of the O-SEE 100k and the O-SEE 75k will need to pick up their packets on Friday.
Late entries are possible on site only upon availability up until 30 minutes before the start. The fee is € 10.00 in addition to the entry fee.
Timing / Evaluation
Timing is done with an electronic timing system contactlessly with a transponder, which is integrated in the start number. Only the timekeeping of the organiser is valid for the results!
Equipment
For all Trail Runs we recommend taking the following equipment with you:
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Mobile phone with the emergency number stored and the possibility to send location data via WhatsApp, SMS or similar application
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GPX-capable phone or navigation watch with the stored track/route data of the respective route
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First Aid Kit (tape bandage, elastic bandage, compress, plaster)
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Closed trail running shoes with tread sole
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Weatherproof clothing
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Running backpack
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Safety whistle
It is compulsory to bring the following equipment:
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100k/75k/50k/25k/16k: Drinking container to receive drinks at the refreshment points
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100k/75k/50k/25k: GPS tracker device (will be available for pickup at the check-in in the start/finish area)
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100k/75k/50k: Water container with at least 1 litre of liquid 100k/75k/50k: Energy gels & bars
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100k/75k/50k: Mobile phone (which must be able to make calls abroad)
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100k/75k/50k: GPX-capable phone or navigation watch with the stored track/route data of the respective route
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100k/75k: Headlamp
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100k/75k: ID and Health insurance card
Refreshment
O-SEE 100k: 11 x food/drink
O-SEE 75k: 8 x food/drink
O-SEE 50k: 6 x food/drink
O-SEE 25k: 3 x food/drink
O-SEE 16k: 2 x food/drink
There are further catering options in the finish area.
For all Trail Runs no cups will be provided at the refreshment points. You must bring your own drinking containers to receive drinks.
Refueling before running is important, which is possible at our pasta dinner the night before between 5:00 pm and 8:00 pm. Reservation is required with the online registration in order to ensure admission (+ € 5.00).
GPS Tracking
All O-SEE 100k, O-SEE 75k, O-SEE 50k and O-SEE 25k participants will be provided with a small GPS tracker device at the check-in in the start and finish area. The tracker must be worn during the entire race and returned after crossing the finish line.
In the case of abandonment of the race, the GPS tracker and the start number must be handed in at a respective refreshment point. In the event of non-return or damage of the GPS tracker, the participant will be invoiced for the amount of € 100.00.
Award ceremony
The award ceremonies will take place in the start and finish area.
Trail Runs
Trophies will be awarded to the top 6 M/F finishers in the overall race of each course and to the first teams DUO (Men, Women, Mix) of the 100k, 75k, 50k and 25k courses.
Time to be announced on site, probably around 3:00 pm.
Light and Kids Runs
The first place winners M/F under 18s to Masters and the top 3 finishers M/F under 6s to under 16s will be honoured. Time to be announced on site, probably around 12:00 noon.
Other
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Dogs are not allowed as companions on the course.
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The conditions of the organisers O-SEE Sports e. V. according to the announcement, competition regulations and organisational guidelines as well as the conditions of participation are binding.