3rd Rock Mercury Jeans Review

© Dan Bailey

Everyone (except Robert Durran) likes a pair of jeans that you can climb in, but still look good down the pub. Combining fashion with function, 3rd Rock's Mercury Jeans certainly tick those boxes. Though pitched at the more casual, style-oriented end of the outdoor market, they still have a practical edge, with a cut and features suited to climbers.

From bouldering and cragging to just going out on the town (a rare occurrence, admittedly) it's no exagerration to say that I have practically lived in my review pair for the past few months. Only with the onset of the winter climbing season have I peeled them off and given them a wash. They may be pretty much all you need in a pair of kick-about climbing jeans, but this is also the smartest pair of trousers in my drawers. Perhaps that tells you as much about me as about them, but the question remains - are these trousers just too nice to trash on the rock?

Excellent cotton legwear for bouldering, cragging or just general life  © Dan Bailey
Excellent cotton legwear for bouldering, cragging or just general life
© Dan Bailey


They're not the spray-on super skinny legwear the yoof seem to like, but Mercury Jeans do feel relatively close fitting if you're used to more voluminous crag trousers, such as the rest of 3rd Rock's range. At first go I found them a bit restrictive, not to say unflattering, and had to go up from my usual size Large/34 inch waist to (for me) an unprecedented XL/36. I'd blame it on my big hillwalker's thighs, only the fit was equally close at the waist and crotch. Perhaps it's an early warning of middle aged spread, but I'd prefer to think 3rd Rock just cut them a bit tight. Once worn however, and certainly after its first wash, the fabric seems to relax a little, and now the XL is a pretty good fit on me, albeit I need a belt for that wide waist (phew!). Coming in sizes XS-XL, and two different leg lengths, there's a pair to fit most men - at least up to my size (but given that I'm not that big, honest, 3rd Rock probably ought to consider an XXL). Unfortunately Mercury Jeans don't come in a female fit.

Step as high as you like, the Mercury is no impediment  © Martin McKenna
Step as high as you like, the Mercury is no impediment
© Martin McKenna

Tailoring is superb, giving you a slim, flattering and (I guess) fashionable cut without limiting movement in any way. The knee is cut with a bit of articulation for high leg moves, while a little diamond panel in the crotch lets you bridge wide with ease. When wearing Mercury Jeans for bouldering or cragging, the only thing restricting my movement is my own inflexibility.

The ankle is on the slim side, which cuts down the amount of fabric flapping about your shoes and makes it easier to see where you're placing your feet.

A double layer at the knee, which is also cut with room to bend  © Dan Bailey
A double layer at the knee, which is also cut with room to bend
© Dan Bailey


Despite the name, and the look, these are not jeans as I'd usually understand the term. Instead of the usual stiff, scritchy denim feel that you'd associate with jeans, the fabric is soft and forgiving. It feels reasonably hard wearing, though of course as with all cotton clothing it is slower to dry than synthetics. That's not something that'd worry me when cragging, bouldering, or indeed heading out on the town - but for me it would rule out the Mercury for mountain routes and iffy weather. The fabric is perhaps slightly thinner than your average high street denim, and certainly more flexible. With 2.5% elastane to 97.5% cotton, there's a subtle stretch to aid with the freedom of movement. It also holds a turn-up well - I generally turn my trousers up when climbing, for a less cluttered ankle.

Double layers on the knees and bum add some longevity in the areas of highest wear. On me the knee patch is positioned oddly high though, running from mid thigh to just below the kneecap, so when I bend my leg the double layer barely covers my knee.

The fabric holds a turnup well  © Martin McKenna
The fabric holds a turnup well
© Martin McKenna

It's worth pointing out that, as with all 3rd Rock's clothing, the cotton used here is organic. If you're worried about the impact of the clothing you buy - and standard cotton is an environmental nightmare - then this is a major selling point. Another way to reduce one's impact is of course to buy fewer high quality items that are built to last, rather than stuffing your drawers with loads of cheap tat. 3rd Rock score highly on this front too. Made in Turkey, the Mercury jeans are well stitched and nicely finished. Though this has been a short test, I can certainly see these trousers lasting a good while, and continuing to look good til they finally fall off me. In terms of longevity, my only suggestion to 3rd Rock would be to consider adding an extra thickness, or some heavier stitching, to reinforce the button hole.


Funky embroidered design on the back pocket  © Dan Bailey
Funky embroidered design on the back pocket
© Dan Bailey

There's not a lot going on here. What did you want? They're jeans. You get the standard jeans pocket configuration - two rear pockets, two hip pockets and that funny little extra hip one that no one knows what to do with (keys? loose change?). Belt loops are well spaced, and the rear loop is much bigger than the rest in order to give you something secure to clip your chalk bag to (I prefer tying mine on with cord to avoid the possibility of landing with a carabiner positioned on my lower back). For boulderers, the only thing lacking is a little slot for a brush. On the plus side, the 'swirly' detailing on one of the rear pockets is cool. If these trousers were meant to be purely functional then I wouldn't even bother mentioning that, but looking good is very much part of their purpose - and I think they really do. I even got a compliment on them from the wife, and it's rare she notices (much leass cares) what I'm wearing!


Far more comfy and practical than standard denim jeans, but better looking by far than your average crag trouser, Mercury Jeans blend fashion and function. £75 is more than I'd generally spend on casual trousers - a lot more - but from the cut of their jib to the quality of their organic fabric, I think the Mercury are worth their price tag. Their active tailoring and stretchy cotton make these ideal legwear for crags, bouders or the wall. Yet there's no getting away from the fact that they also look really good, and you can wear them in civilised settings without feeling in the least bit self consciously outdoorsy. In fact, outside of a mountain day I can't think of an occasion when I would not want to wear Mercury Jeans. I've been living in my review pair for a number of months, almost exclusively. But fundamentally, are they just too good for climbing?

3rd Rock say:

Don't let your trousers hold you back any more – check out the best climbing and lifestyle jean on the market. Introducing the highly anticipated return of 3RD ROCK's Organic Mercury Jeans made for action, relaxation, climbing and the outdoors. Made with our thickest Organic Cotton fabric to ensure full protection against harsh rock. These organic climbing and lifestyle jeans are equipped with top-notch movement enhancement cuts, whether you use your superpowers or not, is up to you. These organic jeans are extra stretchy, so, don't worry, if you need to unleash the Jackie Chan jump kick across the can.

Mercury jeans prod shot 1

Mercury jeans prod shot 2

  • Price: £74.99
  • Sizes: XS-XL (men's only)
  • Short Leg: 77.5cm -79cm Inseam
  • Regular Leg: 82 - 85cm Inseam
  • Sizing advice: Slimmer cut than our other trousers, this will make a difference to the fit on more muscular thighs
  • The perfect staple jean for any climber or outdoor enthusiast
  • Transitional organic jeans from everyday use to climbing or even the splits!
  • Extra strong organic cotton jean weave
  • Reinforced double-layered bum and knees.
  • Diamond-cut-crotch for extra movement.
  • Extra room in the knees to bend with ease
  • Embroidered back pocket pogo
  • Up-cycled jeans patch made from product waste
  • Embroidered fly – look inside your zip for a surprise!
  • Back waistband print 'Our Planet, Our Playground'
  • Fit: Regular to Slim Fit Organic Jean
  • Fabric: 97.5% Organic Cotton / 2.5% Elastane Stretch Twill
  • Colours: black, night (blue), lizard (green)

For more info see

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16 Jan, 2018

£75.00!!!!! :-0

16 Jan, 2018

Seems a perfectly reasonable price.

16 Jan, 2018

Yeah but they ain't your average jeans! They're 'Transitional organic jeans' :)

To be fair £75 ain't bad if they last. I've been through 4 pairs of the £27 decathlon ones which aren't actually jeans but are just so nice to climb in. Ended up buying some moon ones which seem pretty bomb proof but nowhere near as comfy as the decathlon ones. 

16 Jan, 2018

Yep, looking at Moon and Prana offerings, that's about the market price. 

16 Jan, 2018

I managed about four years out of my old Alpkit jeans before killing the knees and about the same lifespan out of my Prana jeans that have just gone through. 

Twice the price of normal jeans but I've worn mine for everyday use as well as gritstone climbing and they owe me nothing. In fact, I've just ordered a replacement pair. Comfy and stretchy enough for climbing without resorting to Ron Hills (shudders).

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