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(The Gear Loop) - Gone are the days of wrestling a paper map into a small waterproof pouch and then having to perform a bout of origami on a walk because you keep wandering off the edge of the page. 

Thanks to the wonders of modern technology, an entire map of the world can be kept in your pocket and unlike a smartphone, it doesn’t run out of charge in a day. 


Enter the Garmin GPSMAP 66i, a device that is so feature-rich, it’d take a lifetime to trawl through them all. 

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With pre-loaded Garmin Topo mapping, it’s possible to plan and navigate extremely complex routes, while satellite communication allows the owner of this device to stay in touch with the outside world, long after mobile phone signals run out. 

Accurate weather, downloadable satellite imagery, multiple Global Navigation Satellite Systems support and a three-inch sunlight-readable colour display make it one mighty powerful machine to take on treks.

Too much? Well, we haven’t quite summited K2 with it, but we have tested it in some truly horrific conditions up in the Scottish Highlands, so you can be safe in the knowledge it won’t let you down when things get a little hairy. 

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Our quick take

The GPSMAP 66i is a hugely capable device that packs a range of features, many of which are likely to only be used by ardent adventurers. We scrolled through most things on offer for the purpose of testing, but rarely found a use for everything this device can do. 

With that in mind, it requires you to spend time with it and learn where everything is and how it works, as the menus can be a little confusing otherwise. This isn't an unbox-n-go product and it still requires a fair amount of mountain skills to remian safe while using it. 

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We can’t mark it down for this reason, because it’s a truly professional grade GPS device pitched at those who expect their devices to work flawlessly when out in the wilderness, and some users will have a requirement for the niche features that it offers.

Garmin GPSMAP 66i review: a powerful device that is a worthy companion for the gnarliest of adventures

Garmin GPSMAP 66i

5 stars - The Gear Loop editors choice
  • A huge array of features
  • InReach communications give peace of mind
  • Very clear screen
  • Highly customisable
  • Expensive for just mapping
  • Menus can be daunting at first
  • Overkill for casual walkers


In the Loop

Everything you need to know about the Garmin GPSMAP 66i in bite-sized chunks:

  • InReach satellite communication
  • Multi-GNSS satellite support
  • Detailed maps of the world
  • TopoActive Maps show detailed terrain
  • 35 to 200-hour battery life
  • Built to withstand the gnarliest adventures
  • Screen visible in harsh light
  • Altimeter for elevation data, barometer to monitor weather and 3-axis electronic compass
  • High-res satellite imagery available 
  • Plan routes and waypoints from device
  • Connect to smartphone to send messages

Built tough

Garmin is at the top of the class when it comes to anything with GPS functionality, developing products for everything from the fitness sector to aviation, its expertise is unparalleled. In fact, we’ve been handed Garmin devices that we have no clue what to do with, but they help someone, somewhere do their job.

The GPSMAP 66i is the flagship model in the range of handheld mapping devices and it certainly feels it. It has a reassuring heft in the hand without being too heavy. In fact, just holding it made us feel like hardcore explorers. 

The whole thing is shrouded in a tough rubber bumper, which is ready to fend off knocks and bumps, while an oversized SOS button on the side suggests the kind of environments it will be used in and seem to warrant the use of rugged, exposed Torx bolts holding the chassis together. A carabiner can be clipped onto the back to allow the device to be hung from a backpack strap for easy access.

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The main body of the 66i is made from an eye catching orange polymer that means the whole device is rated to MIL-STD 810, which in plain English means that its burly enough to withstand 28 different stresses as set out by the US military. 

That could mean explosions, but more importantly, it has the ability to withstand rain, humidity, sand and dust and the fantastically named “multi-exciter test”, which is essentially exposing it to a series of shocks, drops and scrapes. This thing means business.  

Finally, all wrapped up in this rubber and polymer safety cocoon is a battery that is good for 30 hours of tracking at 10 minute intervals and a monstrous 200 hours if you increase the tracking interval to 30 minutes.

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Screen burn

The three-inch screen is bright, contrasty and fares well in direct sunlight, making it perfect for following maps when the golden orb in the sky appears. 

The nine chunky rubber buttons on the face of the device below the screen are used to navigate through the menus, as the panel isn’t touch sensitive, something we’d normally like to see, but because of the environments that this device could be used in, accidental screen inputs could be disastrous. 

Touch screens also don’t fare well with either rain or gloved fingers, both of which will be in abundance in the great outdoors. 

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Mo' maps, no problems

It’s under the luminous orange polymer of the GPSMAP 66i where thing get really interesting. Not only is it a GPS unit, using Garmin’s InReach technology that allows you to stay in touch with base camp via messages when there’s no phone signal. It also allows friends and family to track your progress in real time with a host of metrics. 

Crucially it means that you can trigger an SOS to a 24/7 global emergency response centre, which will co-ordinate your rescue with local emergency services. We never had to use this feature up on the mountains of Scotland, thankfully, but knowing help is at hand however far from civilisation we strayed was very reassuring. 

All of the InReach features require a subscription to the Iridium satellite network, but with plans starting from £12.99 a month, it really is a no brainer.

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Maps, however, are free. Maps of the entire world, in fact. You read that right - maps of 195 countries… in your pocket. Fully zoomable and incredibly detailed, too.

A few years ago, you would have paid a fortune to have access to worldwide mapping and now its included. Granted, you won’t want to be doing any hardcore navigation from these base maps, but Garmin offers their excellent TopoActive mapping alongside them, which offers routable roads and paths, places of interest and a whole slew of other handy information. 

Our device came preloaded with TopoActive maps of Europe, with maps of pretty much anywhere else in the world available to buy. The detail of the base maps is excellent, even providing the tidal range of coastal environments, which was very handy when plotting routes across such terrain. 

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A pro performer 

On the whole, the map is very clear and easy to understand, however one gripe we did have was the lack of contour lines. 

Having trawled through the extensive menus for a while, it wasn’t immediately clear if we’d missed the button to switch them on or they simply weren’t included. It turned out to be the latter, but fortunately, the 66i has support for a range of open source mapping formats, so it was simply a case of finding the right file that contained the contour information and copying it to the device via the micro SD card. 

It’s also worth mentioning that the 66i has a 16GB of internal memory, but its recommend to install additional maps to the SD card and leave the internal memory for activity recording. 

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It’s this open source-ness that makes the 66i a hugely customisable product for almost every outdoor pursuit. A quick glance at the accessories range for the device cements this, mounts are available for cars, bikes, boats and most other things you’d want to navigate in or on.

While on the topic of customisation, almost every screen can be tailored to each user, allowing data fields to be shown or hidden when needed and placed in different locations on the crisp display. 

This is something that hardcore adventurers will really appreciate, because when faced with extreme environments, your kit needs to work with you and the ability to have all the data you need on one screen, rather than delving into menus constantly, is a small thing that can make a huge difference. 

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That said, those menus are a little daunting at first glance, with pages and pages of icons and sub-menus that take a lot of getting used to. 

In general operation, there’s no real need to be delving into the main menu all the time, as pressing the page button brings up a carousel of quick access tools such as the compass, altimeter and InReach messages. 

Phone home

It’s not just traditional mapping and navigation that the 66i offers. Delve into the menus and there’s an almost overwhelming array of features. Geocaching co-ordinates can be accessed directly from the device, as can sunrise or sunset times, tide times and the ability to create routes from existing routes or waypoints without having to even touch your phone. 

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The 66i is a very accomplished device on its own but connect a smartphone via Bluetooth and it becomes even more powerful. The Garmin Explore website and smartphone app is a great way of not only planning routes, but uploading specific GPX files and other navigational tools to the device.

What's more, the InReach messaging service is much more user-friendly when paired with a smartphone, as you then can use your phone's touchscreen to type out messages, rather than painstakingly punching in a letter at a time using the 66i's old-fashioned D-pad.

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A smartphone connection also allows the 66i to download satellite imagery of any area, which makes navigating in tricky conditions that much easier. It’ll also pull a weather forecast direct to the device to help make more informed decisions on multi-day escapades. The 66i can even take into account your planned route and offer forecasts along the way based off current speed and elevation. 

A rapid connection 

We’ve used a few of Garmin’s other GPS and InReach devices but we noticed just how quick the 66i connects to satellites - it’s almost instant upon powering up the device, which is seriously impressive given it can locate you down to 40m in a flash. We’ve had a play with an InReach Mini and the same couldn’t be said for that, often taking five minutes or more to find the satellites. 

For this test, we took the 66i on a number of hikes, some on paths and some completely cross country, relying only on the maps and contours to keep us on the straight and narrow. In both environments, the device performed admirably - the bright screen providing clear mapping and the buttons allowing us to zoom in and out, and pan around the map to chart our progress.

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We did find the buttons a little difficult to press at times when wearing thick gloves, but soon got used to it. Audible notifications can be set up to alert you when diverging from the set route, much like many of Garmin's smart watches and bike computers. It's a great feature, saving us from checking the map every five minutes to confirm headings.


To recap

An impressively powerful GPS device that offers so much more than just route-finding. The ability to contact friends and family - or even rescue services - is a huge draw for those pushing exploration further. The amount of customisation options the 66i offers is mind boggling and we loved being able to tweak every aspect of the device, from individual screens to adding new maps with extra information. However, don’t be lured into a false sense of security, you can just switch the device on and you’re suddenly a 21st century Ernest Shackleton, the 66i takes time to set up, get to grips with and fully understand.

Writing by Matt Buckley.