Grizzlyman
Olesna reservoir, Frydek-Mistek, Czech Republic · May · Independent (Czech; Extreme Triathlon Series listing)
Why people love it
- Remote Beskydy bike course with +2,700 m (8,860 ft) over 183 km (114 mi) and Pustevny descents
- Small, friendly field of 22-24 starters with returning champions
- Reservoir swim at a 4 a.m. start, then a forest trail run with about 1,560 m (5,120 ft) of climbing
- Single-venue logistics inside FM Sportfest, alongside half, team and duathlon races
Watch out for
- Very cold conditions possible: 12 °C (54 °F) water and 3 °C (37 °F) air in 2025
- Course figures differ by source: 183 or 185 km (114 or 115 mi); 2,700 or 3,680 m (12,070 ft) gain
- Course changes (Lysá hora reroute 2023, new run 2026); a winner went off-route in 2026
- Only about 22-24 full starters and very few independent athlete reports
- Date has moved between May and July
Race
How racers feel about it, how well it is run, and how it treats a first timer. Counts for 27% of the overall score.
- Racer satisfactionLoved4.1
Every athlete quoted praises the scenery, swim, bike or organisation. All sources are the organiser or local press, and only 22-24 people start. · Low confidence
- OrganizationWell run3.9
Quick reroute in 2023 and a calm halving of the swim in cold 2025 weather drew praise. In 2026 the winner took a wrong turn. · Low confidence
- First timer friendlyExperts only1.2
Tiny field of 22-24 starters, 2,700 m (8,860 ft) of bike climbing, a hilly trail run, a 4 a.m. start and cold risk. · Medium confidence
Course traits, not part of the score
- PR potentialVery slow1.3
Winners take 10:26-11:42 versus about 8:00-8:30 on fast courses, with 2,700 m (8,860 ft) of bike climbing and a trail run. · Medium confidence
- Course easeVery tough1.5
2,700 m (8,860 ft) of bike gain over 183 km (114 mi), a rocky trail run with 1,560 m (5,120 ft) of climbing, and cold. · Medium confidence
Swim
Wetsuit odds, water temperature, calm, and the experience of the start. Counts for 15% of the overall score.
- Wetsuit legalAlmost always4.9
Water was 11-12 °C (52-54 °F) in 2025 and 2026, so a wetsuit is effectively always allowed in late May. · Medium confidence
- Water temperatureUncomfortable1.6
11-12 °C (52-54 °F) in 2025 and 2026, very cold. The 2025 swim was halved. · Medium confidence
- Calm waterMostly calm4.2
A sheltered reservoir with no chop reported. · Low confidence
- Swim easeModerate3.0
Two 1.9 km (1.2 mi) laps in the dark at 4 a.m. and in cold water. No currents. · Low confidence
- Swim experienceFine3.3
The 2026 winner praised the swim, though it is cold, dark and a small mass start. · Low confidence
Bike
Road surface, closures, scenery and wind. Counts for 19% of the overall score.
- Road surfaceMixed3.0
Public roads in the Beskydy hills. No complaints found. · Low confidence
- Road closuresMostly open2.4
Public roads, with closure level not documented. · Low confidence
- Bike scenerySpectacular4.5
Athletes praise the Beskydy hills and views. · Medium confidence
- WindMostly calm3.7
A valley and hill route. Wind is not mentioned, though ridges may be exposed. · Low confidence
Course traits, not part of the score
- Bike speedSlow2.2
2,700 m (8,860 ft) over 183 km (114 mi). A 2023 athlete averaged about 30 km (18.6 mi)/h (19 mph) on the replacement route. · Medium confidence
- Bike flatnessMountainous1.3
Officially +2,700 m (8,860 ft) over 183 km (114 mi), which is mountainous. · High confidence
- Bike simplicityTechnical2.3
Long, cold, fast descents from Pustevny (one athlete was shaking in 2025) and the Ondřejník loop. · Low confidence
Run
Crowds, aid stations, conditions underfoot and scenery. Counts for 13% of the overall score.
- Crowd supportSparse2.0
A rural trail run with a small field. A festival crowd gathers only near the reservoir. · Low confidence
- Aid stationsStandard2.8
The 2026 winner went without water for a while. No other complaints found. · Low confidence
- Run sceneryBeautiful4.0
Forest and Beskydy trail. Athletes liked the new 2026 route. · Low confidence
- Run conditionsHard1.5
Rocky forest trail with 1,560 m (5,120 ft) of climbing after 183 km (114 mi) of riding. Navigation errors have been reported. · Medium confidence
Course traits, not part of the score
- Run flatnessHilly1.6
About 1,560 m (5,120 ft) of gain on 42 km (26 mi) of forest trail. An older listing says 2,400 m (7,870 ft). · Medium confidence
Conditions
Air temperature, how predictable the weather is, setting, and spectating. Counts for 15% of the overall score.
- Air temperatureWarm or cool2.8
Race-day temperatures ranged 3-25 °C (37-77 °F). The 4 a.m. start at 3-11 °C (37-52 °F) is cold, and afternoons are mild. · Medium confidence
- Weather reliabilityUnsettled2.3
A cold snap halved the swim in 2025, 2023 was hot and 2026 was mild. The date has moved between May and July. · Medium confidence
- Venue beautyLovely4.0
A Beskydy foothills setting. · Low confidence
- Spectator friendlySome viewpoints3.0
Held within the FM Sportfest at the reservoir, with loops allowing some viewing. · Low confidence
Course traits, not part of the score
- Low altitudeLow3.9
The reservoir is at about 300 m (980 ft), and the bike climbs to Pustevny near 1,020 m (3,350 ft). · Medium confidence
Stay and travel
Hotels, walkability, getting there, and the town around the race. Counts for 11% of the overall score.
- Hotel availabilityGood4.2
Frýdek-Místek (about 55,000 people) and Ostrava have rooms, and the field is small. · Low confidence
- Hotel valueGood4.0
Czech regional pricing. · Low confidence
- WalkabilitySome driving3.0
The venue is on the city outskirts, and hotels are a short drive away. · Low confidence
- Travel easeOne connection3.2
Ostrava airport (OSR) is about 30 km (19 mi) away. Prague is about 4 h by road or rail. · Low confidence
- LogisticsSimple4.3
One venue and one transition at the reservoir, in a festival format. · Medium confidence
- Town and foodFine3.3
City amenities in Frýdek-Místek, plus festival food on site. · Low confidence
Key facts
- Location
- Olesna reservoir, Frydek-Mistek, Moravian-Silesian, Czech Republic
- Typical month
- May
- Latest or next date
- 29 May 2027
- Organiser
- Independent (Czech; Extreme Triathlon Series listing)
- Field size
- About 24 athletes
- Distances
- 3.8 km (2.4 mi) swim, 180 km (112 mi) bike, 42.2 km (26.2 mi) run
- Swim venue
- Olesna reservoir (reservoir)
- Water temperature
- 0–12 °C (32–54 °F)
- Swim start
- mass
- Swim laps
- 2
- Bike climbing
- 2,700 m (8,860 ft)
- Bike laps
- 2
- Key climbs
- Pustevny; Ondrejnik loop
- Run climbing
- 1,560 m (5,120 ft)
- Run laps
- 2
- Run shade
- mostly forest in 2026
- Air temperature
- 3–25 °C (37–77 °F)
- Altitude
- 300 m (985 ft)
- Nearest airport
- Ostrava (OSR), 30 km (19 mi) away
- Where to stay
- Frydek-Mistek
- Booking
- Stay in Frydek-Mistek or Ostrava; no race-week pricing reports found.
What racers and reviewers say
- Patriot Magazin (Czech)Raced 2023 · article · Positive
Recap of the 1 July 2023 edition: 23 starters jumped into Olesna reservoir at 4 a.m. A last-minute reroute through the Beskydy (incl. an Ondrejnik loop) replaced Lysa hora and was called demanding but attractive. Hradecky won in 11:34 in surprisingly hot weather; Vabrousek said the course was fast with about 30 km (18.6 mi)/h (19 mph) bike averages and praised the organisers' quick fix; debutant Kotopulu loved scenery and run.
- Grizzlyman official recap 2025Raced 2025 · article · Positive
Organiser recap of a freezing edition: 3 °C (37 °F) air and 12 °C (54 °F) water forced the swim to be halved. 22 started, 20 finished, including the sole woman in about 16 hours. Winner Hradecky took his second title in 10:26:37; third-place Vabrousek described shaking on cold Pustevny descents. Race director admitted doubts about running a fair race in the cold.
“Grizzlyman is a beautiful race”
- Frydecko-Mistecky a trinecky denikRaced 2026 · article · Positive
Local-press report on 23 May 2026: 24 starters from five countries at 4 a.m. in 11 °C (52 °F), warming later. Winner Jilek (11:42) liked the swim, bike and atmosphere but took a wrong turn on the new mostly-forest run and was briefly without water. Vabrousek liked the new trail and called it properly extreme; organiser wants to keep the route.
- Magazin POSITIV (Czech)Raced 2026 · article · Positive
Preview describing Grizzlyman as one of the toughest Czech triathlons, drawing pros and amateurs, based at the Olesna boathouse with 2,700 m (8,860 ft) of bike climbing and about 1,560 m (5,120 ft) on the run. The 2026 festival added team, aquabike and duathlon options and a family programme.
- extremnizavody.czRaced 2026 · article · Positive
Czech extreme-race site headline report on the 2026 edition won by Jilek; only headline-level content was readable, corroborating results and venue.
Sources
Pages we used for facts and ratings. See how we rate.
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