X CxM Sierro vs Ultra Trail Bosques del Sur
X CxM Sierro (24km, 1100m D+) vs Ultra Trail Bosques del Sur (70km, 3700m D+). Side-by-side comparison: distances, elevation, difficulty, mandatory gear and registration. Which one suits you best?
Advanced
AdvancedPhysical profile
| X CxM Sierro | Ultra Trail Bosques del Sur | |
|---|---|---|
| Date | 3 May 2026 | 30 May 2026 |
| Terrain | Mountain | Trail |
| Difficulty | Advanced | Advanced |
| Max elevation gain | 1,100m D+ | 3,700m D+ |
| Max ITRA | — | 3 |
Distances — X CxM Sierro
| Name | Km | D+ | Max Time |
|---|---|---|---|
| CxM 24K | 24 | 1,100 | 4h30 |
| MiniCxM 12K | 12 | 680 | 4h30 |
Distances — Ultra Trail Bosques del Sur
| Name | Km | D+ | ITRA | Max Time |
|---|---|---|---|---|
| Ultra 70K | 70 | 3,700 | 3 | 17h |
| Marathon 42K | 42 | 2,438 | 1 | 10h |
| Half 21K | 21 | 1,190 | — | 5h |
| Mini 10K | 10 | 600 | — | 3h |
| Kids 4K | 4 | 100 | — | 1h 30min |
Logistics & costs
Pack 360 — Services
Registration
X CxM Sierro
No recommendations
Ultra Trail Bosques del Sur
No recommendations
Accommodation
X CxM Sierro
No recommendations
Ultra Trail Bosques del Sur
No recommendations
Gear
X CxM Sierro
Salomon Speedcross 6Recommended for bothSalomon
Salomon ADV Skin 12Salomon
Salomon Soft Flask 150 mlSalomon
Ultra Trail Bosques del Sur
- Salomon Speedcross 6Recommended for both
Salomon
Nutrition
X CxM Sierro
Maurten Gel 100Maurten
Precision Fuel & Hydration PH 1500Precision Fuel & Hydration
Dátiles Medjool DorimedDorimed
Ultra Trail Bosques del Sur
Bocadillo de Guayaba Gourmet LatinoGourmet Latino
Transport
X CxM Sierro
No recommendations
Ultra Trail Bosques del Sur
No recommendations
Car Rental
X CxM Sierro
Recommended for both
Recommended for both
Ultra Trail Bosques del Sur
- Recommended for both
- Recommended for both
Insurance
X CxM Sierro
No recommendations
Ultra Trail Bosques del Sur
No recommendations
Body Care
X CxM Sierro
Julbo AerospeedRecommended for bothJulbo
Buff CoolNet UV+Recommended for bothBuff
BodyGlide Original Anti-Chafe BalmBodyGlide
Ultra Trail Bosques del Sur
- Julbo AerospeedRecommended for both
Julbo
- Buff CoolNet UV+Recommended for both
Buff
Salomon Cross VisorSalomon
Sun Protection
X CxM Sierro
Recommended for both
Recommended for both
Ultra Trail Bosques del Sur
- Recommended for both
- Recommended for both
Terrain and elevation
X CxM Sierro is classified as Mountain, while Ultra Trail Bosques del Sur is Trail — different technical demands on paper. On its longest distance, Ultra Trail Bosques del Sur climbs around 53m per km versus 46m/km on the other race — the higher that ratio, the steeper and more technical the climbs tend to be.
Location and travel
X CxM Sierro and Ultra Trail Bosques del Sur both take place in Andalusia, about 80km apart in a straight line — close enough to scout one course while training for the other, or fold both into a single trip.
Entry price
Ultra Trail Bosques del Sur is the cheaper entry, starting from €5 versus €18 for X CxM Sierro — a €13 gap on the entry-level distance.
Time of year
Both races take place in May, so you'll have to pick one per season. X CxM Sierro falls right in its region's recommended window. Ultra Trail Bosques del Sur falls right in its region's recommended window.
Mandatory gear
The two mandatory gear lists don't overlap at all. X CxM Sierro additionally requires windbreaker, hydration capacity of at least 1L, mobile phone with battery; Ultra Trail Bosques del Sur additionally requires frontal, cortavientos, silbato and 3 more.
Summary
If you're looking for a longer distance, Ultra Trail Bosques del Sur is the choice. If you prefer a shorter and more accessible race, consider X CxM Sierro. In terms of elevation gain, Ultra Trail Bosques del Sur is the more demanding option. Both races offer a complete Pack 360 with everything you need for race day.
Frequently asked questions
Which is harder, X CxM Sierro or Ultra Trail Bosques del Sur?
When does each race take place?
How many distances does each race offer?
What type of terrain does each race have?
Do I need the same mandatory gear for both?
Plan your race