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9.2 oz / 4mm drop / $170
The Dirt: With monster teeth on the outsole, the S-Lab Fellcross 3 is designed for the muckiest trails you can throw at it. What’s most miraculous about it, as many of our testers raved about, is its exceptional light weight, given the burly protection it offers—in the laterally supportive upper (sturdy on aggressive turns and steep climbs or descents), rock plate and cleat-like lugs.
The solid upper is mostly waterproof—great for snowfields or rainy days, not so great for quick draining or hot weather. Salomon’s signature quick-lace system allows easy on/off.
Best For: Fell running, cross-country or obstacle races; wet, muddy or snowy terrain; steep trails; 5Ks to half-marathons.
Fit: Snug, glove-like fit; true to size, but slightly narrow through the midfoot and toebox.
- “I love that Salomon went all out for a specific, serious trail shoe! The grips are totally worth it on steep dirt inclines or declines. As light as the shoe is, the soles are protective and substantial enough for off-road trails. I could feel the trail, but rocks or roots didn’t hurt as they do with minimalist shoes. I ran a sprint-distance obstacle-course race in these shoes and they performed amazingly on the ski slopes.”
—Sarah von Harz
- “The sides of the shoe are completely waterproof. I was most impressed with this when I traversed a couple of snowfields high in the Continental Divide. There’s a rubber citadel surrounding the bottom of this shoe. Unless snow was coming in from the top, it wasn’t getting in the shoe.”
- “After wearing this shoe on rocky and rough terrain for a few weeks, they still look brand new. The rubber on the body and bottom of the shoe makes them extremely durable. When I crossed through streams and muddy sections my foot stayed relatively dry, and the fit was not compromised after they dried out from these wet and muddy conditions. I wish I had this shoe for my college cross-country racing days!”
Testers on Fit
- “The shoe is lightweight, low-profile, responsive and fits my foot like a glove.”
- “They were narrow in the area right above the arch by the ball of my foot. The toebox was comfortable and the length was perfect.”
- “The toebox is roomy which is nice for a few reasons: it gives your toes room to feel the trail better on the run, even through the substantial treads, but it also allows your feet to swell a bit without getting crowded as they can on long runs.”
—Sarah von Harz
- “I was very impressed with how the Fellcross fit. The heel pocket did not allow for any slippage, and my arch and toebox always felt snug in place during every run.”
- “The area around the toebox was pretty tight—not as tight as the last model, but I still noticed the outside metatarsals on one foot radiating some pain like they were squeezed too tightly. I don’t have a very wide foot, either. Granted, this went away when I got a few miles in, but it could deter some people and I never saw the harm in a bit wider toebox.”
Testers on Tread
- “On a wet day after it rained, I had no problem running in the mud, over roots and through rocky areas. Mud gathered underneath but came off in clumps before I lost traction. The traction also holds on steep angles.”
- “The tread is outstanding with the V-design lugs. They are able to grip on slick rocks and mud, yet release the organic matter once clear of the bog. The TPU toecap protects against rocks, roots and other trail hazards even as I haphazardly kicked rocks down the mountain. These shoes are definitely made for mud and slog; they are a bit unforgiving on rocky sections or pavement to and from the trail. High alpine would be a perfect place for them with the soft trails, creek and snow crossings.”
- “I wore this shoe during a 10K trail race in Beaver Creek, Colorado. This race covered a variety of terrain including a long downhill on a mountain access road that was all loose rocks and gravel. Since I was racing I was going as fast as possible on this downhill. I did not feel a single slip on this descent and did not lose any traction. This saved my turnover and stride a lot of energy, and put my mind at ease since I was not worried I would slip out. There were also muddy sections with wet rocks and roots. Once again, these shoes gripped this terrain so well. I also noticed how amazing the grip was while running on grass.”
- “The shoe really ate up grassy hills on the ridges above treeline. Wet grass, dry grass, it didn’t matter. It also excelled in loose gravel and small scree. We encountered snowfields on the north face of Grey’s Peak; we’re talking about mid-July snow on a 14er that gets annihilated by tourists—it had a hardpacked path cutting across frozen corn. But even a tourist could cross the snowfield with ease in these shoes. The mud surrounding the snow was no match for the shoe either. [However] I did not feel comfortable when crossing the bare granite near the tops of the peaks. It just felt precarious to have that much tread on solid rock. I had to hammer a dried out dirt road in the last couple of miles and it was unpleasant to say the least. Keep this shoe on the softer, wetter terrain and away from solid rock or hardpacked trails.”
Testers on Downsides
- “The waterproofing means that it does not breathe like a mesh-topped, light-duty trail shoe. While spinning some laps at my local park in these shoes with some medium-weight wool running socks on a hot day, my feet were cooking.”
- “Cushion is not the strong point of the Fellcross, but to be fair, the Fellcross is not meant to be a soft ride shoe, especially on dry trail conditions.”
- “I did not feel the shoe had great breathability. The black upper and lack of mesh contributed to bad drainage and hot feet.”