Big Agnes Three Wire Hooped Bivy review: great things come in small packages

Big Agnes Three Wire Hooped Bivy: first impressions

The Big Agnes Three Wire Hooped Bivy is a tiny shelter suitable for whipping up when you need to get your head down. Offering little in the way of frills, this bivy is not designed for whiling away weekends next to a waterfall or for basking in the glorious sunshine at the foot of a mountain. It’s built for fast and light adventures – to get you and up and down mountains be it in hiking boots, trail running shoes or on a mountain bike. It’s here to help you get a safe and reasonably comfortable night’s sleep when your priority is to push on. And I think it absolutely delivers. 

Weighing a frankly ridiculous 538g at a minimum, the Big Agnes Three Wire Hooped Bivy comes with four pegs and a singular pole, which is all you need to turn this into a shelter capable of keeping you warm and safe on any four-season backpacking trip, regardless of the weather. Coming with three guy lines, you’ve also got the additional option to fasten down any of the components that might otherwise get blown around. And if you’re moving with poles, as I was on one testing trip, you can use them to lash-out the guy lines at the foot end of the shelter to raise the footbox and increase internal space.

Designed from a fully recycled, ripstop polyester material, the fly sheet of the Big Agnes Three Wire Hooped Bivy is also reliably waterproof. Naturally, when it comes to these sorts of tents, you’re inevitably going to get some water inside when setting up in the rain – and then you’re going to have to wait it out until it stops again to avoid even more coming in. But for a shelter for use in decent conditions when there’s only a fleeting chance of rain, the Big Agnes Three Wire Hooped Bivy is excellent. The material is very breathable, soft to the touch and looks great when pitched, despite it being the opposite of stealthy – it only comes in a super-loud, bright red color.

Coming in at $349 / £339 when bought directly from Big Agnes, the Three Wire Hooped Bivy is quite pricey for such a small shelter. That being said, the R&D Big Agnes have invested in creating such a durable, small and light shelter is palpable from the moment you open the bag. And while it might not be for everybody, the tiny pack size, the comfort and practicality it affords combined with the low weight make it a great choice for anyone who values portability over anything else, such as die-hard fastpackers or bikepackers, or people who are more interested in moving quickly than sleeping soundly.

Big Agnes Three Wire Hooped Bivy: in the field

Aside from its low weight, one of the most impressive features of the Big Agnes Three Wire Hooped Bivy is its pack size. It’s tiny. Without the pole (which I stored down the side of my pack), the whole thing can be squashed down to about the size of a large grapefruit – impressive!

And it’s also incredibly easy to put up. In fact, you could sleep in this by just rolling it out on the ground, although adding the pole only takes a few seconds and keeps the mesh off your face through the night. 

With the guy lines at the foot end tied out, you also have ample room at the bottom of the tent, and being 76cm wide, there’s more than enough space for an extra wide sleeping pad as well as any bits and bobs you want inside the shelter with you, such as power banks, water, food or spare clothes. When compared with similar models, such as the Outdoor Research Helium Bivy, the Big Agnes Three Wire is almost 10cm wider, which makes a huge difference if you need to spend any length of time in one of these. 

When it comes to ventilation, Big Agnes have added a huge opening at the head end that allows for maximum airflow. In heavy rain or driving wind, it might not be possible to open this wide, but with it down, we had no condensation whatsoever inside the bivy on the nights that we tested it. What’s more, when the weather is extra calm, you can open up the zipper around the hoop and pull the waterproof fly down like a blanket, which makes it great for easily getting in and out of the bivy, as well as for adding some extra ventilation on warm, bug-free nights.

One thing to bear in mind, however, is the fact that this tent is void of any frills whatsoever. There are no pockets, nor are there any fancy hanging lines or lashes to hold the doors open. This bivy has been designed to be as lightweight, as small and as durable as possible. 

Because of its small size and complete lack of vestibule, it’s also not possible to cook inside one of these shelters, nor can you bring your pack in with you in the rain (unless you don’t mind it lying over your chest). Therefore (though this applies to every bivy bag out there), this style of shelter might not be the best in rainy environments or in regions where the weather can turn at any moment, such as in the UK. 

To mitigate this, many people pair them with a lightweight tarp, but having to bring additional gear can make whole package comparable to a lightweight tent, in terms of both price and weight. 

At 211cm long, the Big Agnes Three Wire Hooped Bivy is also plenty long enough for most users. In fact, a friend who comes in at 6ft 6in (198cm) also spent a night in the Big Agnes and was happy to report back that he had more than enough room through the night. 

For me, being a bang-average 5ft 10in (177 cm), I found the internal space to be plenty for both me, a pad, a thick bag and some nick-nacks, and I even managed to squash my small 30L Ultimate Direction fastpacking pack down at the foot end to keep that out of the elements through the night. Were I to take this on a multi-day hike, however, it wouldn’t be possible to do the same with a larger 50L-60L hiking pack. That would have to tough it outside.

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