We spent 9.5 hours reading reviews from experts and users. In summary, this is what runners think:

5 reasons to buy

  • The sizing scheme of the New Balance Summit Unknown worked well with the expectations of many testers.
  • Several consumers noted that the upper unit was sufficiently breathable.
  • Those who have tried it greatly appreciated the lightweight nature of this running shoe.
  • The traction capacity of the outsole tread was deemed reliable. People also stated that it even handled technical trails with ease.
  • The upper unit was able to drain water well, a reviewer noted.

3 reasons not to buy

  • The tongue unit tended to deviate from its regular position, so several users had to cut anchor points on it to allow the laces to loop through them.
  • A tester felt that the width was a bit narrow.
  • According to a reviewer, the thin insole tended to slide forward and bunch up against the toe box.

Bottom line

People were mostly happy with the performance of the New Balance Summit Unknown. They welcomed its breathable and quick-draining upper unit, the sure traction of the semi-aggressive outsole, and the lightweight construction. Conversely, some runners were taken aback by the deviating tongue unit while others didn’t appreciate width profiles. Overall, this neutral trail shoe is divisive, but it’s still got its fair share of appreciation.


Terrain: Trail
Arch support: Neutral
Weight: Men: 8.6oz | Women: 7.4oz
Heel to toe drop: Men: 10mm | Women: 10mm
Pronation: Neutral Pronation
Arch type: High arch
Strike Pattern: Heel strike
Distance: Competition
Heel height: Men: 26mm | Women: 26mm
Forefoot height: Men: 16mm | Women: 16mm
Release date: Apr 2018
Brand: New Balance
Width: Men: Normal, Wide, X-Wide | Women: Normal, Wide
Price: $110
Colorways: Black, Blue, Green, Orange, Purple
Special editions: 1 special editions
Small True to size Large
See more facts


Among the better Trail running shoes
A popular pick

Expert Reviews

Experts are runners, who post reviews at youtube, directly at RunRepeat or at their own websites. Each expert is categorized from level 1 to level 5 based on expertise. See stats on expert reviews and how we calculate scores here.

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93 / 100 based on 5 expert reviews

  • 90 / 100 | Mark Highland

    New Balance Summit Unknown: Unwrap your feet and get closer to nature

    More photos

    Trail running is where my heart really lies. Those ephemeral moments that last so briefly that you wish you had someone to experience that fleeting moment with you.

    I ended up with the New Balance Summit Unknown after some great customer service from New Balance. I was set on using a pair of the Hierro V3 fresh Foam for my races last year but had a bit of a nightmare with them.



    I think I may have had a defective pair, or they just didn’t work with my forefoot strike. But I ended up with the sole of my foot bruised and then to add to the issues the sole of the right shoe started coming away from the upper.

    Cue the customer service team at New Balance, and after an exchange of emails and images, I was refunded for the shoe, and I ordered the Summit Unknown as a replacement.

    Initial impression

    Out of the box, the bright orange trainers meant that I wasn’t going to be missed on the trails. Eye-catching and the reinforced toe box is reassuring you that those rogue snags won’t be catching your precious toes easily.


    The upper material is lightweight but is not waterproof. This does drain and dry quickly. So, your feet don’t feel like they are swamped when you step in that inevitable puddle.

    As many people have mentioned the tongue of these is quite short. But unlike many, I have not experienced any slippage or stones in the shoes. The collar of the shoe is lightly padded and with this shoe being aimed at faster/race runs its intention is evident.



    I have run about 120 miles in these shoes on a mixture of trail types along the South Downs Way and the transitions between surfaces have been smooth, even though the shoe is a trail shoe using it along the road to get to or between the trails is comfortable.

    This probably comes down to the Revlite midsole of the shoe, which although not of the maximal design provides good cushioning and protection for the feet. This in part is helped by the footplate in the forefoot to help nullify the hazard of stones impacting the sole of the shoe.



    The amount of cushioning in the midsole does lead the shoe to feel responsive, and your feet feel in touch with the trail.


    The grip on the outsole of the Summit Unknown is provided by 5mm lugs that perform well on the shales and gravel of the South Downs Way. Whilst easily being able to cope with softer sections of the trail when required.

    I have found limits to the shoe grip at the more extreme end of the mud spectrum. But there are other shoes out there that excel at that which I would use if I needed to. Over wet rocks, the grip is exceptional and gives you the confidence to push hard without fear of slipping.



    This shoe suits me as a forefoot runner, with a need for the shoe to flex in the forefoot. I was surprised at how flexible this shoe was even though it has the incorporated footplate.

    Over shale, gravel, and mud, the grip will not let you down and wearing the shoe on the road to the trails is painless due to the flexibility of the shoe. The only limitation of the shoes I have found has been in the extreme mud and at 175lbs.

    I would have doubts on how my feet would cope with any ultra-distance events in these. I think though that is my limitation rather than the shoes, as I have worn them on the trails for 22 miles without any issues.

    At the moment, these are my go-to trail shoes, and I don’t have any doubt that they will get used until they are gardening shoes. The Summit Unknown will appeal to those looking for a lighter/faster shoe for the trails.

    Many will be drawn to the maximal shoes of the moment, but to me, they wrap your feet in a bubble and shut you off from the trail experience. Unwrap your feet and get closer to nature with these Summit Unknown. You might like it.

    This expert has been verified by RunRepeat. Reviews are neutral, unbiased and based on extensive testing.

  • 82 / 100 | Tim Wright

    Desperately seeking a New Balance Leadville replacement

    More photos

    Alas, the New Balance Leadville v3 ceased production, and the quest continues for a worthy replacement.

    As a middle-aged, highly competitive, trail runner with a history of calf strain problems my criteria are:

    • A decent drop (preferably 8mm+)
    • Adequate cushioning for 60km+ runs
    • A trail shoe with sufficient traction and protection for a variety of terrains
    • A lighter weight shoe (preferably <300g) for performance



    The New Balance Summit Unknown has been touted as a natural successor to the Leadville, being a high-end trail show from the same manufacturer.

    But how does it measure up in practice?

    My Testing

    This review is based on at least a dozen runs totalling over 200km on hilly, sometimes muddy and sometimes rocky terrain. I have not tested the shoes on runs for more than two hours.

    My experience with shoes lacking midsole cushioning is the basis of my decision for the maximum run duration.

    However, it is still important to note that the lack of cushioning contributes to the light weight of the shoes.

    Comfort, Midsole and Insole

    Arguably the most important aspect of any shoe, I consider the Summit Unknown’s comfort fairly average. On the plus side, they were not uncomfortable out of the box.

    Also, the fit is reasonable for my medium to slightly wide feet. Some reviewers have noted issue with the tongue dropping/scrunching up.



    I have not experienced this although the neoprene-style tongue is one of the least comfortable tongues I have encountered in trail shoes.

    Overall, the shoe has a slightly rigid, plastic feel. Additionally, the uppers are not particularly soft or comfortable.

    The Summit Unknown boasts a highly desirable 10mm drop. This drop is crucial for a runner susceptible to calf tears and calf strain. The drop reduces the pressure on the calves.

    However, I don’t find these shoes particularly comfortable. It's because of the overall modest heel and forefoot height combined with a relatively hard, unforgiving midsole.

    In this regard, I would not use them for runs over two hours as the cushioning is insufficient for this purpose.

    I have not experienced any movement of the insole in wet conditions. The shoes are performing well in this aspect.


    This criterion is a huge plus for the Summit Unknown. The shoes weigh 245g. This is well under the weight of the Leadvilles (293g) and the majority of trail running shoes.


    The mighty Leadvilles boasted a Vibram outsole that was hard-wearing and the uppers lasted for a long time. It is a little early to tell if the Summit Uknown will go the distance.

    Nevertheless, the outsole does not appear to show noticeable wear after 200km on the trails. However, there are some tell-tale signs of fabric abrasion occurring on the uppers.



    These abrasions can be found at a logical location, around the flex-point on the big-toe side of both shoes.


    Another huge plus for the Summit Uknown is the good amount of traction from the lugged outsole. This is one area in which the Leadville had a chink in the armour. 



    The Leadville did not grip well in muddy and wet conditions. The Summit Unknown perform very well in this regard


    The very light weight of these shoes and modest stack height might be expected to yield a highly nimble shoe.

    However, my experience is a little disappointing in this regard. It might be due to the hard midsole and plastic-like uppers.

    Wearing it feels a little like wearing clogs, albeit light and grippy ones. A little more flex in the midsole might help in this regard.


    The Summit Unknown is certainly not an expensive shoe compared to other brands’ top-end models.

    However, the true test for value is not only the ticket price but the longevity of the shoe and enjoyment whilst wearing them. In this regard, the Summit Unknown performs reasonably well.

    Summing up

    Unfortunately, the New Balance Summit Unknown is not, for me, a worthy successor to the New Balance Leadville for longer trail runs. They are a little more minimalist.

    Thus, it does not provide the same level of comfort or enjoyment of the trail. However, it is still worthy of consideration for shorter off-road runs given their low weight and superior traction.

    The quest continues…

    This expert has been verified by RunRepeat. Reviews are neutral, unbiased and based on extensive testing.

  • 92 / 100 | Road Runner Sports | | Level 4 expert

    I just got this out on the trails. It's super fun, lightweight and protective ride.

  • 95 / 100 | Road Trail Run | | Level 5 expert

    The Summit Unknown makes for a great race shoe or up tempo trainer for up to mid distance on a wide variety and especially technical terrain. Despite the initial blister issues, the upper of the Summit Unknown is softening and breaking in to the point where it is less of a problem, but pressure remains and I find myself being cautious.

Become an expert

  • The Summit Unknown is a reliable New Balance trail running shoe that’s created for the neutral runner. It features a trail-optimized design to bring confidence over a variety of outdoor terrains. The outer tread makes use of a sticky rubber compound to provide grip on dry and wet surfaces.
  • Cushioning is handled by the RevLite foam which is a full-length compound that offers responsive cushioning and shock attenuation. Affixed between the midsole and outsole is a high-density forefoot plate for protection against debris and irregular surfaces.
  • The upper unit features a synthetic mesh to provide a secure and well-protected coverage. It has tiny ventilation holes that allow air into the foot-chamber. Complementing the external mesh is a set of thin overlays and underlays.

The New Balance Summit Unknown makes use of standard measurements to accommodate the preferences of consumers. Lengthwise, it adheres to the regular expectations. The women’s version has these widths: B – Medium and D – Wide. The men’s iteration features the D – Medium and 2E – Wide variants. The semi-curved shape of this shoe’s last mimics the natural curvature of the human foot.

The outsole unit of the New Balance Summit Unknown utilizes the HydroHesion rubber compound. This full-length material is specially designed to provide traction on wet surfaces. Having this layer would potentially increase confidence when tackling slippery trails and paths.

A semi-aggressive lug-pattern allows this shoe to traverse different types of topography easily. Also, the multi-directional configuration of these nodes permits confident uphill climbs and downward excursions.

RevLite is a lightweight material that is advertised as more responsive and sturdier than heavier midsole compounds. It’s been designed to resist early sagging or breakdown.

The Rock Stop® is a layer of dense material that’s placed in the forefoot section. Its purpose is to protect the underfoot from rough surfaces and trail debris. It also attenuates impact shock and diffuses the energy generated by such a force.

A foam insole is placed above the primary midsole unit. It can be replaced or removed entirely.

The façade is mostly made using a synthetic mesh which is a lightweight material that offers breathable coverage. It has a semi-closed construction to improve its durability.

Fantom Fit is an overlay-and-underlay system that’s composed of two materials that have been combined using a no-sew method. The goal of this add-on is to assist in providing a secure yet customizable fit.

Protecting the forefoot section of the New Balance Summit Unknown is the Toe Protect™ compound, which is a thin layer of rubber that acts as a shield against sharp objects on the trail.

The tongue and collar are padded. These two sections hold the foot in place and prevent it from wobbling inside the foot-chamber.

Soft fabric lines the interior of this shoe. It’s crafted to stave off hot spots and skin irritation.

A pull tab is placed on the back portion of the collar. This loop makes it easy to wear and remove the Summit Unknown.


Jens Jakob Andersen

Jens Jakob is a fan of short distances with a 5K PR at 15:58 minutes. Based on 35 million race results, he's among the fastest 0.2% runners. Jens Jakob previously owned a running store, when he was also a competitive runner. His work is regularly featured in The New York Times, Washington Post, BBC and the likes as well as peer-reviewed journals. Finally, he has been a guest on +30 podcasts on running.