Purple Mountain Observatory is bringing its debut footwear silhouette back for another season, with the Calyx™ returning on 29 October 2026. Developed alongside Vibram, the technical shoe combines an unconventional rubber construction with outdoor-ready performance, while its latest iteration introduces three colourways and a refreshed sole treatment.
First released last winter, the Calyx established a different approach to outdoor footwear, using specialist materials and a seamless construction to move away from the traditional layered sneaker design. For its second outing, Purple Mountain Observatory keeps the original foundation while also introducing some new elements, including a classic gum sole and a dual-colour speckled finish.
Built for Unpredictable Terrain
The Calyx was first developed around the idea of simplifying construction without compromising performance. Its seamless waterproof upper is engineered from Vibram’s advanced StratX formula, which allows the waterproof upper to be sculpted from a single sheet of specialised rubber. By removing conventional stitching and layered construction, the design creates a streamlined shell intended to handle changing outdoor conditions.
The sole unit is equally performance-focused. A Vibram Grivola outsole combines lightweight construction with Vibram Megagrip compound, providing grip across both wet and dry surfaces. Designed for varied environments, the Calyx is suited to everything from forest trails and muddy ground to exploration when the weather turns unpredictable.
A Conversation with Purple Mountain Observatory
With the Calyx returning for a second season, we spoke to the Purple Mountain Observatory team about the thinking behind its first footwear silhouette, the collaboration with Vibram and the response to last year’s release.
The Calyx is Purple Mountain Observatory’s first footwear silhouette. What inspired the brand to move into footwear, and how did the original idea take shape?
Footwear had always been part of a plan for PMO, whether it was through collaboration or otherwise. As a brand we want to be able to offer equipment which can be used in both the outdoors and in day to day, whether that’s through apparel, footwear, or other equipment. The idea started with sandals to be honest, it started with a want for a shoe which is less for hiking and more for relaxing (after hike). We then looked at how we can make it functional (mega-grip sole, waterproof etc) and this naturally led into the Calyx.
The Calyx returns for a second chapter with updated sole treatments and three colourways, what was the reason behind these updates?
The Calyx for us was a huge success last year, our first step into footwear and we couldn’t have asked for it to have gone better. When Matt (Braun – Founder) & the team revisited the idea of it, we wanted to bring some newness, I remember some crazy ideas being flung about, but then we had to be realistic. For us the different sole treatments is a playful but subtle touch. We have also brought back a limited amount of the OG colourways but this is exclusive to us. I think the Calyx will be something we always experiment with.
The Calyx was developed in collaboration with Vibram. How did that partnership come about, and what made Vibram the right partner?
We were introduced to the Vibram team via a close friend of the brand, we shared imagery of soon to be released campaigns and saw a synergy right of the bat, we had a similar approach to how we wanted to tackle the outdoors, especially in such a crowded market.
I think whenever PMO look’s at collabs, we always think who is the master of their craft – who is owning the bag world, who is owning the shoe game and so on. And for us, Vibram is top for technology within the field. They’re constantly exploring new ideas at their labs, and this came as a real inspiration to us.
What does the name Calyx mean to Purple Mountain Observatory?
The Calyx is the outer whorl of a petal (on a flower), it protects the inner bud, it was something Matt thought up a while ago and he had the name trademarked if we were to ever do a subline of PMO (forward thinking ey) , we were throwing names around and none of them quite hit. And then I remember one of us saying why not just use Calyx? and it really felt right. Everything kind of clicked from then, and it’s been picked up really nicely.
It’s nice to have a name / phrase that you can say you own as a brand, it’s quite unique.
What feedback from the first Calyx release has been the most useful in shaping this new version?
Haha honestly, just more colourways and more sizes! It’s been great, and we thank everyone for their support and love for the shoe. Who knows what’s next!
Growing Something Extraordinary
For the new campaign, Purple Mountain Observatory turns to a rather unexpected corner of outdoor culture: giant vegetable growing. The imagery explores the dedication, patience and occasional absurdity involved in producing something far beyond the ordinary, following people who are willing to get their hands dirty in pursuit of ambition.
That world of competitive vegetable growing demands persistence and willingness to work with the elements nature gives, offering a natural connection to the Calyx’s practical construction.
The Purple Mountain Observatory Calyx launches on 29 October 2026, available through the brand’s website and selected retailers.
