Four Summits 72K Aid Station Planner
All 10 Four Summits 72K checkpoints pre-loaded. Enter your goal finish time to get estimated arrival times at every aid station.
Enter a goal Four Summits 72K finish time and get estimated arrival times at every checkpoint - 72 km with around 4,600 m of climbing, with crew and drop-bag points flagged.
Turns every arrival into a clock time and every cutoff into a margin.
Terrain changes how the goal time is shared between segments, not the total. One surface everywhere cancels out.
Checkpoints (10)
Cutoff Sat 11:00
Cutoff Sat 17:00
Cutoff Sat 21:00
Cutoff Sun 00:30
Cutoff Sun 02:00
Four Summits 72K
Goal 14:45 · Start Sat 06:00
- Crew may meet you at
- Rusca 39.0 km, by Sat 14:00
- Transrarau 52.5 km, by Sat 16:59
- Drop bags
- Rusca 39.0 km, by Sat 14:00
| Checkpoint | Dist (km) | D+ (m) | Km-effort | Arrive by | Clock | Cutoff | Buffer | Leave by | Seg time | Seg pace/km |
|---|---|---|---|---|---|---|---|---|---|---|
| Start | 0 | 0 | - | 0:00:00 | Sat 06:00 | - | - | - | - | - |
| Bucovina Eco Retreat | 8.6 | +498 | 15.6 | 1:37:40 | Sat 07:37 | - | - | Sat 08:05Set by Zugreni | 1:37:40 | 11:19 |
| Rarau 1likely hiking (pace) | 13.6 | +822 | 13.2 | 3:00:35 | Sat 09:00 | - | - | Sat 09:28Set by Zugreni | 1:22:55 | 16:37 |
| Zugreni | 23.2 | +81 | 14.6 | 4:32:15 | Sat 10:32 | Sat 11:00 | 28 min | Sat 13:31Set by Rusca | 1:31:40 | 9:35 |
| Poiana Prisloplikely hiking (pace) | 31.6 | +1102 | 21.7 | 6:48:36 | Sat 12:48 | - | - | Sat 15:47Set by Rusca | 2:16:22 | 16:11 |
| Rusca | 39.0 | +43 | 11.5 | 8:00:53 | Sat 14:00 | Sat 17:00 | 2h59 | Sat 18:01Set by Transrarau | 1:12:16 | 9:43 |
| Cabana Giumalaulikely hiking (pace) | 46.0 | +799 | 15.0 | 9:34:52 | Sat 15:34 | - | - | Sat 19:35Set by Transrarau | 1:34:00 | 13:36 |
| Transraraulikely hiking (pace) | 52.5 | +394 | 13.4 | 10:59:06 | Sat 16:59 | Sat 21:00 | 4h01 | Sat 21:39Set by P. Mesteacan | 1:24:14 | 12:50 |
| P. Mesteacan | 68.5 | +527 | 27.1 | 13:49:10 | Sat 19:49 | Sun 00:30 | 4h41 | Sun 01:04Set by Câmpulung Moldovenesc (Finish) | 2:50:04 | 10:41 |
| Câmpulung Moldovenesc (Finish)likely hiking (pace) | 72.0 | +334 | 8.9 | 14:45:00 | Sat 20:45 | Sun 02:00 | 5h15 | - | 0:55:50 | 15:44 |
Bucovina Eco Retreat
Sat 07:37Leave by Sat 08:05Set by Zugreni
- Dist (km)
- 8.6
- D+ (m)
- +498
- Seg time
- 1:37:40
- Seg pace/km
- 11:19
Rarau 1likely hiking (pace)
Sat 09:00Leave by Sat 09:28Set by Zugreni
- Dist (km)
- 13.6
- D+ (m)
- +822
- Seg time
- 1:22:55
- Seg pace/km
- 16:37
Zugreni
Sat 10:32Cutoff Sat 11:0028 minTight
Leave by Sat 13:31Set by Rusca
- Dist (km)
- 23.2
- D+ (m)
- +81
- Seg time
- 1:31:40
- Seg pace/km
- 9:35
Poiana Prisloplikely hiking (pace)
Sat 12:48Leave by Sat 15:47Set by Rusca
- Dist (km)
- 31.6
- D+ (m)
- +1102
- Seg time
- 2:16:22
- Seg pace/km
- 16:11
Rusca
Sat 14:00Cutoff Sat 17:002h59
Leave by Sat 18:01Set by Transrarau
- Dist (km)
- 39.0
- D+ (m)
- +43
- Seg time
- 1:12:16
- Seg pace/km
- 9:43
Cabana Giumalaulikely hiking (pace)
Sat 15:34Leave by Sat 19:35Set by Transrarau
- Dist (km)
- 46.0
- D+ (m)
- +799
- Seg time
- 1:34:00
- Seg pace/km
- 13:36
Transraraulikely hiking (pace)
Sat 16:59Cutoff Sat 21:004h01
Leave by Sat 21:39Set by P. Mesteacan
- Dist (km)
- 52.5
- D+ (m)
- +394
- Seg time
- 1:24:14
- Seg pace/km
- 12:50
P. Mesteacan
Sat 19:49Cutoff Sun 00:304h41
Leave by Sun 01:04Set by Câmpulung Moldovenesc (Finish)
- Dist (km)
- 68.5
- D+ (m)
- +527
- Seg time
- 2:50:04
- Seg pace/km
- 10:41
Câmpulung Moldovenesc (Finish)likely hiking (pace)
Sat 20:45Cutoff Sun 02:005h15
- Dist (km)
- 72.0
- D+ (m)
- +334
- Seg time
- 0:55:50
- Seg pace/km
- 15:44
Highlighted rows use a pace heuristic (>12 min/km / >19 min/mi) - likely hiking by speed, not grade. The grade-based power-hike cue is ≥15% (see GAP and Incline tools). Times are distributed proportionally by km-effort.
Leave by is the latest you can start the next segment and still make every cutoff ahead of you at this pace - often set by a station further on, not this one. It does not yet subtract the time you spend stopped, so treat it as the optimistic edge.
Cutoff buffers are estimates from your goal time and published barriers. Courses and barriers change - verify against the official race guide.
Next step
About Bucovina Ultra Rocks by UTMB - Four Summits 72K
Bucovina Ultra Rocks by UTMB - Four Summits 72K covers 72 km with around 4,600 m of elevation gain, starting in Câmpulung Moldovenesc, Romania. The overall cutoff is 20 hours.
Crew access is allowed at Rusca (39.05 km) and Transrarau (52.52 km). Drop bags are available at Rusca.
Checkpoint data approximate - verify against the current official race guide at bucovina.utmb.world before your race.
The science behind km-effort pacing
Most runners build race pacing plans by dividing total distance evenly - which ignores the fact that an uphill kilometre takes far longer than a flat one. This planner uses TrailMath's enhanced km-effort model to distribute your goal time proportionally by effort, not by distance.
The km-effort formula for each segment is: distance_km + gain_m/100 + loss_m/200. This is TrailMath's extension of the standard ITRA gain-only formula (model TM1, where the descent divisor is a published convention), which adds descent cost because steep technical descents carry real eccentric load. A 5km segment with 500m of gain and 200m of loss has an effort of 5 + 5 + 1 = 11 effort-km - equivalent to running 11km flat. Time is allocated proportionally to this effort score.
Why gain and loss have asymmetric costs. Minetti et al. (2002) mapped the metabolic cost of inclined locomotion across gradients from -45% to +45%. The key findings: metabolic cost rises steeply above 15-20% uphill grade, making power hiking more energy-efficient than running on steep climbs. On descents, eccentric muscle loading (quads acting as brakes) creates its own metabolic cost - steep technical descents are far more demanding than the same gradient on a smooth fire road. The gain/100 + loss/200 asymmetry in the formula reflects this - gain is more costly per metre than loss, but loss is not free.
Power hiking threshold is flagged at segments where your computed pace exceeds 12 min/km (19 min/mile). This threshold corresponds to the crossover point where walking biomechanics become more efficient than running on steep uphill terrain. Strategic power hiking on marked segments preserves leg muscle for descents and reduces overall race time compared to running everything.
This km-effort model is the same formula used in TrailMath's training engine for load calculation (following Dan Johnston's asymmetric elevation scoring methodology), ensuring consistency between how your training load is measured and how your race effort is planned.
Minetti AE et al. (2002). Energy cost of walking and running at extreme uphill and downhill slopes. J Appl Physiol. 93(3):1039-46. Minetti AE et al. (1995). Mechanical determinants of gradient walking energetics in man. J Physiol. 481(Pt 1):235-43. ITRA. km-effort formula. International Trail Running Association. itra.run
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