In one sentence: September is one of the best times to go down the Sella. The first half is summer without the crowds; the second, golden autumn with the river almost to yourself. We tell you the difference between the two halves of the month, the deal with the water, and why so many people who know the river come back precisely now.
August has the sun and the buzz, but also the queues. That is why anyone who has been down the Sella before will tell you a secret: September is, for many, the best month of the year. Summer is still there for the first fifteen days, but the tide of people has gone with the back-to-school routine. The river breathes. So do you.
That said, September has two very different faces depending on the half, and it is worth knowing before you choose a date. We tell you honestly, from Arriondas and with more than 25 years closing the season in this month.
The two faces of September: first vs second half
This is the most important idea in the whole guide. September is not a uniform month: it changes a lot between the 1st and the 30th.
- First half (1-15 September): basically late summer. Mild water, days still long, riverside bars open, gentle warmth. But with a fraction of the people of August. If you want summer without the crowds, this is your window.
- Second half (16-30 September): autumn arrives. The flow rises a little with the first rains, the water cools, the days shorten and the valley begins to turn golden. More intimate, more photogenic, with a wetsuit when it is needed. A real beauty for anyone after peace and quiet.
Both versions are wonderful: you just have to choose the one that matches what you are after. If you are unsure which month to pick, we compare them all in the best time to do the Sella descent and in the Sella descent in summer.
Water and weather in September · what you will find
What we usually see each September in Arriondas and along the navigable stretch:
- Air temperature: 20-26 °C in the first half, 16-22 °C in the second. Still pleasant for paddling.
- Water temperature: mild (15-17 °C) until mid-month; cooler from the second half onwards.
- Flow: normal to low early in the month, rising a little with the first autumn rains. A slightly higher flow makes the descent smoother.
- Light: the famous golden September light, softer and warmer than the vertical August sun. It is the best of the year for photos.
Our wetsuit-free season runs from 15 June to 28 September: during the first part of the month the water is mild and you do not need one. From late September, when the water cools, we give you the wetsuit free as you set off if the monitor judges it necessary. It is not an extra: it is included when it is needed. If you come in the last week of the month, take it for granted that they will offer it to you.
Why September is such a special time
These are the reasons why so many people who know the Sella choose September over August:
- The river almost to yourself. With the schools going back, the crowds drop sharply. Where in August you see a hundred canoes, in September you see ten. No queues at ticket desks, changing rooms or coaches.
- Nature at its best. The valley begins to turn golden, the woodland changes colour and the river has a silence that is impossible in high summer.
- Photographer's light. The warm, low September light makes any photo on the river come out beautiful. If you love your camera, this is your month; we recommend stopping at Pozo del Arco.
- Same price, more calm. There is no surcharge for coming in September, and you take home a far more peaceful experience.
Who to go down with in September: families, couples, photographers
- Families. The first half is ideal with children (from 5 years old and 1.15 m): mild water and few people. If the little ones are already back at school, there is always the weekend plan. More in Sella descent with children.
- Couples. September is perhaps the best month for a romantic getaway on the Sella: calm river, golden light and a valley that feels like yours alone.
- Photographers and lovers of calm. The second half, with its light and its silence, is hard to beat.
- With a dog. Your pet comes down free with its canine life jacket. In September, what is more, there are fewer horseflies than in August.
Booking your descent in September
In September the booking pressure drops a great deal compared with August, so you have room to manoeuvre:
- Booking 2-4 days ahead is usually enough, and often the same day is possible if there is a slot. By website, WhatsApp, phone or email (not at the desk without notice).
- Choose your route: Mini (7 km, ~2h) or Complete (14.5 km, ~4h), both at the same price. You have the highlights on the route map and the timings in how long it takes.
- Arrive between 10:30 and 12:30, the best window of the day. Remember that the river closes at 18:00 by order of the Confederación Hidrográfica del Cantábrico.
- 2026 price: €35 adults, €25 children aged 5 to 12, pets free. No seasonal surcharge. If you want the day with no friction, look at the Premium 10:30-12:30 window.
If you are coming from far away, we help you on how to get to Arriondas, and if you want to know what to pack, on what to bring to the Sella descent. We are the team from Arriondas you can read about on about us, with 147 real reviews (4.5★).
If you like the idea of a calm river, golden light and Asturias at its most serene, September is waiting for you. Book your descent here and we will see you on the water.
What you ask us most
- Can you do the Sella descent in September?
Yes, and it is one of the best times of the year. The season stays open throughout September. The first half is practically summer (mild water, riverside bars open) but with far fewer people than in August. The second half brings the autumn mood: a slightly higher flow, cooler water and the valley beginning to turn golden. Book here with a real-time calendar.
- Is the Sella water cold in September?
It depends on the half. In the first half of September the water is still mild (similar to August) and you do not need a wetsuit. From late September the water cools down and then we give you the wetsuit free when it is needed (our wetsuit-free season runs from 15 June to 28 September). The monitor decides, looking at the water on the day.
- Is everything open in September, the riverside bars too?
In the first half, yes, most of the riverside bars along the route are still running. From the middle to the end of the month some start to close. If you come in the second half, it is worth bringing your own food in the dry barrel just in case.
- Are there fewer people in September than in summer?
Far fewer. With the schools going back, the crowds drop sharply from the first weekend of September. You have the river almost to yourself, without the August queues at ticket desks, changing rooms and coaches. For couples and photographers it is the ideal time.
- How much does the Sella descent cost in September?
The same price as all year round: €35 adults and €25 children aged 5 to 12, with pets free. No seasonal surcharge. It includes the canoe, paddle, life jacket, return transfer, parking, changing rooms and lockers. Detail in prices and what is included.
