Three days of rain in the Monts d’Arrée: what held up and what gave way

Three days of rain in the Monts d’Arrée did not defeat all of my kit. Above all, they taught me a distinction: keeping water out and keeping your things dry are two separate problems. My jacket turned clammy without any leak I could find. My boots ended up damp inside. My sleeping bag and night clothes, on the other hand, stayed dry, protected inside the rucksack.

The most useful thing was not some impressive piece of equipment. It was a stubborn line between wet and dry, a few adjustments made early enough, and a pair of socks I forbade myself to walk in.

From Huelgoat to Saint-Rivoal, three wet days

Three days and two nights in the Monts d’Arrée, in Brittany, from Saturday 20 to Monday 22 September 2025. Setting off from Huelgoat, passing not far from Lake Brennilis, the Saint-Michel reservoir, then Mont Saint-Michel de Brasparts and Lake Drennec, and finishing at Saint-Rivoal, where someone came to pick me up by car. Not a loop, then, but a crossing. About 29 miles (47 km) in all, according to the route I traced afterwards on Map Planner: around 12 miles (20 km) on the first day, about 10 (16 km) on the second and 7 (11 km) on the third.

Enlarge diagram

Two nights wild camping, one of them on private land, with the owner’s permission.

Enlarge photo

The rain was not constant. On the first day, mostly drizzle: fine, light rain. On the second, rain and showers, with some fairly long bright spells. The heaviest rain fell on the second night, and it was still raining on the morning of the third day. Between one day and the next, the boots never had time to dry.

It was around 10 to 15 °C. Nothing measured to the decimal point, and no rainfall readings either: I am not about to turn a sodden sleeve into a weather station.

The kit itself was nothing exotic.

This is not a product ranking. It is what I had on my back, and how the whole lot behaved when evening never brought a chance to dry out.

The jacket: a soaked surface does not prove a leak

On the first morning, the drops were still beading on the jacket. By evening, some patches had darkened. Inside, my top was damp between the shoulder blades.

My first instinct was to blame the jacket. Yet I saw no trickle in one spot, and no mark clear enough to show where water had got in. Mostly, I had been walking too fast, with the vents closed.

A membrane jacket does two jobs at once. The membrane is the barrier against water. The water-repellent surface finish, often known as DWRDurable water repellent: a surface treatment that makes water bead up on the outer fabric., helps drops bead up rather than soak into the fabric. GORE-TEX, which explains this for its own garments, says that losing water repellency does not, on its own, mean the membrane has lost its waterproofing; a saturated outer fabric still makes you less comfortable and gets in the way of moisture escaping [5].

Enlarge photo

On the second day, I changed the way I was walking before thinking about changing jackets. I took off a layer I no longer needed while on the move, opened the vents and, above all, slowed down at the first sign of overheating, rather than waiting until my back was wet.

It worked better, though it was no miracle: my top still was not dry, but the damp was no longer building up as much. What gave way here was, first of all, comfort at the surface and the way I managed my effort. Not waterproofing whose failure I could actually have demonstrated.

The boots: water does not need to get through the membrane

On the first evening, my socks were damp. On the second day, the tops of my socks were properly wet. I had put my overtrousers on too late: the bottoms of my trousers had had time to soak up water from the vegetation, and covering the boots afterwards obviously did nothing about the water already inside.

A waterproof boot is still open at the ankle. REI, the American outdoor co-op, recommends gaiters or waterproof overtrousers to protect your socks and the tops of your boots [6]. That does not seal anything, but it deals with a way in that the membrane cannot close off.

So I cannot put all the damp down to a leak. Sweat, water coming in from the top and a possible seep through the boot all feel much the same. Without checking each separately, declaring a ‘faulty membrane’ after two days would be a convenient diagnosis, not a serious one.

At camp, I took out the insoles. By morning, they were still damp. The pair of socks kept for the night stayed in its bag: I did not sacrifice it for a few minutes of comfort in a wet boot.

The rucksack: the rain cover was only the first barrier

Under the cover, the rucksack did not stay dry for all that. The shoulder straps and back panel were wet, and an outside pocket had water sitting at the bottom. I could not work out which way that water had come: the rain, the run-off and the rucksack being opened again and again all had several chances to play a part.

The protection that counted was inside: the large dry bag, which keeps the night things apart from the rest of the load. The wet flysheet travelled in a separate bag, outside that dry space. This precaution answers a known limitation: a rucksack can be cut from waterproof fabric without its seams, zips and openings being waterproof too. REI recommends protection inside the pack, and dry bags for the most sensitive kit, even with a rain cover [6].

Enlarge photo

The real weak point was my organisation. On the first day, I had packed a snack too far down. To get at it, I opened the main compartment and handled several things with wet hands. The lesson: whatever you need during the day goes where you can reach it without opening the protected part. There is no need to unpack your entire bedroom to find a snack.

What held up: the sealed-off sleeping kit and night clothes. What gave way: my belief that a rain cover was enough to turn the whole rucksack into a dry space. Outside pockets are damp zones, best accepted as such, not places to leave anything fragile unprotected.

The tent: a dry night does not mean dry walls

On the first night, nothing came up through the ground. Yet when I woke, the inside of the flysheet was covered in condensation. That is not a contradiction: a tent can keep the rain off and still build up moisture. Even a well-ventilated shelter often holds some under the flysheet and under the floor, as REI points out [8].

My mistake was more mundane than a fault in the fabric. I had left the wet jacket in the porchThe space covered by the flysheet in front of the inner tent, where boots and rucksack are kept., right against the door of the inner tent, and the entrance got soaked. On the second evening, I drew a clear line: wet boots and clothes in the porch, away from the inner tent. A small cloth dealt with the flysheet and the drips near the entrance.

One more thing to check when pitching: a groundsheet must not stick out beyond the tent floor, or it will catch the rain. REI advises folding the overhanging edges of an ordinary tarpaulin under the floor [8]; our guide to tarp set-ups applies the same rule.

The habits that keep you comfortable

Here is the routine I would keep to from the very first evening.

1. Get the pitch ready before opening the rucksack. The tent and its accessories come out without anyone touching the dry clothes, and the dry bag is closed again as soon as something has been taken out of it.
2. Finish setting up before getting the sleeping kit out. Tension, entrances, wet areas: the sleeping bag is not a place to park things while you sort out the rest.
3. Only change under cover. Night clothes stay protected until the moment you put them on; keeping this dry reserve is also one of REI’s tips for walking in the rain [6].
4. Keep what wipes apart from what must stay dry. The flysheet cloth never goes in with the clean clothes.
5. Pack the wet things separately the next morning. The flysheet is folded away without touching the sleeping kit; a short lull gets rid of some of the drops, but it does not dry the fabric.
6. Do not raid the dry reserve to walk in. Putting on your night clothes to set off again would only push the problem on to the next evening.

These habits take some care, especially when all you want is to crawl into the tent as fast as possible. Their whole point is to stop one hurried move from spoiling the hours that follow.

What I would check before heading out again

After those three days, I would not replace my whole kit list. I would start by looking at the limits that showed up, one at a time.

For the jacket, the first check would be the water repellency. GORE-TEX suggests a simple test: sprinkle it with water and see whether the water beads up, or soaks into the fabric and leaves darker patches [5]. The manufacturer then recommends suitable care, following the garment’s label first; the instructions vary with the construction, and a treatment that suits one jacket does not suit them all [10].

For the boots, I would first look for better protection at the opening, and put the overtrousers on before the bottoms of my legs were soaked. Persistent damp would then call for a separate check, not a verdict based on wet socks. For the rucksack, I would keep the rain cover, but treat the inner dry bag as the real protection. For the tent, I would pitch it again in the dry, to check the tension, the seams and the floor.

Finally, getting home does not mean the job is done. REI recommends drying the tent completely before storing it: damp encourages mould and damages the waterproof coatings [8]. The boots, too, deserve a slow dry, as Nikwax advises [7].

By the end of the third day, then, I had not found a way to keep everything dry. I had learned to choose what absolutely had to stay dry, then to organise every move around that priority.

My night socks had not covered a single mile. Yet they were the pair that had worked best.

Worth watching

GORE-TEX explains why a jacket whose water-repellent finish has worn off can feel damp and clammy, as if it were leaking, then shows how to restore that finish on outerwear, gloves and footwear.

The video is hosted by YouTube (Google): nothing loads until you play it, and Google may then set cookies.

Erik Vadas-Gauden

The one who started Outfarer

Outfarer started with Erik, who launched it with a few passionate friends. A nature lover above all, he writes about the subjects closest to his heart and reviews a good part of the magazine, including every survival and bushcraft article before it is published.

All their articles