EuroVelo 13 - Iron Curtain Trail - part Bulgaria South: which way and when to ride
The best month for EuroVelo 13 - Iron Curtain Trail - part Bulgaria South is October: 79% of days were dry with highs of 10–30 °C. In October the wind barely favours either direction — on average 0.2 km/h along the route (ERA5 2006–2025, daytime 9:00–18:00).
Weather by month
| Month | Good days | Rain days ≥ 1 mm | Rain, mm | Avg high | Days ≥ 30 °C | Days < 10 °C | Daylight, h |
|---|---|---|---|---|---|---|---|
| January | 14% | 20% | 78 | 5 °C | 0% | 83% | 9.5 † |
| February | 29% | 21% | 67 | 7 °C | 0% | 67% | 10.6 † |
| March | 48% | 28% | 87 | 11 °C | 0% | 41% | 11.8 |
| April | 62% | 35% | 81 | 15 °C | 0% | 12% | 13.3 |
| May | 60% | 40% | 93 | 20 °C | 0% | 1% | 14.5 |
| June | 49% | 40% | 92 | 25 °C | 12% | 0% | 15.2 |
| July | 50% | 21% | 50 | 28 °C | 30% | 0% | 14.9 |
| August | 54% | 16% | 34 | 28 °C | 32% | 0% | 13.8 |
| September | 76% | 17% | 47 | 23 °C | 7% | 0% | 12.4 |
| October | 79% | 18% | 75 | 17 °C | 0% | 7% | 11.0 |
| November | 56% | 19% | 74 | 12 °C | 0% | 33% | 9.8 † |
| December | 19% | 19% | 84 | 7 °C | 0% | 77% | 9.2 † |
Best months are all months within 3 percentage points of the best one. † less than 11 hours of daylight — long stages get tight.
Wind by month
| Month | Wind near Novo Selo → near Ivaylovgrad, km/h | Headwind > 15 km/h, near Novo Selo → near Ivaylovgrad | Headwind > 15 km/h, near Ivaylovgrad → near Novo Selo | Better way |
|---|---|---|---|---|
| January | +0.8 | 0% | 1% | either |
| February | +0.5 | 1% | 1% | either |
| March | +0.7 | 1% | 1% | either |
| April | +0.2 | 1% | 1% | either |
| May | +0.1 | 1% | 1% | either |
| June | −0.6 | 1% | 0% | either |
| July | −1.3 | 1% | 0% | either |
| August | −2.2 | 2% | 0% | near Ivaylovgrad → near Novo Selo |
| September | −0.9 | 1% | 0% | either |
| October | −0.2 | 0% | 0% | either |
| November | +0.3 | 0% | 1% | either |
| December | +0.5 | 0% | 1% | either |
Stages
The route is split into 4 stages of about 100–150 km between towns; each stage has its own page.
| Stage | km | Best month | Tailwind near Novo Selo → near Ivaylovgrad in October, km/h |
|---|---|---|---|
| 1. near Novo Selo → Hadzhidimovo | 112 | October | +1.6 |
| 2. Hadzhidimovo → Smolyan | 116 | September | +0.3 |
| 3. Smolyan → Dzhebel | 114 | September | −1.1 |
| 4. Dzhebel → near Ivaylovgrad | 114 | October | −1.7 |
How to read the numbers
Wind is the 10 m wind of a 25-km grid cell, daytime hours 9:00–18:00 local solar time; at saddle height in a sheltered valley it is weaker, on a coast or ridge stronger. A positive value is a tailwind. ERA5 slightly over-counts days with ≥ 1 mm of rain (by about 5–7 percentage points) and underestimates daily highs by 1–2 °C. Good day = less than 1 mm of rain between 9:00 and 18:00 (riding hours, local solar time) and a high between 10 and 30 °C; rain at night or in the evening does not spoil it.