Galileo and GLONASS on the Garmin GPSMap 66s

GPS and GLONASS satellite pages

Satellite pages from a Garmin GPSMap 66s showing the GPS and GLONASS status screens

The GPSMap 66 series are the first trail receivers from Garmin to use both the Russian GLONASS and European Galileo satellite navigation systems. On the Satellite Setup page, you have a choice of using GPS (NavStar) only, or GPS+GLONASS, or GPS+Galileo. The advantage of using Galileo or GLONASS with GPS is that you have more satellites in the sky, which improves the quality of your position fix, and increases the receiver's accuracy and ability to maintain a position fix with a partial view of the sky. Note the 10-foot accuracy in the above screenshots. In my location in northern Arizona, more GLONASS satellites are usable than Galileo satellites, but you'll need to experiment under your own conditions.

Using the Garmin GPSMAP 66 in the Field

I have a GPSMAP 66S, but what I have to say here applies to the 66ST as well- the only difference between the models is that the 6ST adds Garmin Topo maps. I prefer to load my own maps from, which are more detailed than Garmin's 100K maps and are free. So, when I refer to the GPSMAP 66S below, I mean both models.

Before I get started, let me say that the positives in this unit far outweigh the negatives, at least for my use. The core function, that of locking onto satellites and determining your position, is significantly improved over the already excellent GPSMAP 64 series.

New Garmin GPSMAP 66 Series

As my regular readers know, I'm a fan of the button-operated GPSMAP series from Garmin. So I was excited to see the new GPSMAP 66 series released. At first, it didn't seem like this was much of an upgrade from the GPSMAP 64, but a closer look revealed that some long-awaited features have been added. So I decided to order one to check it out. Until it arrives and I can evaluate the unit in the field, here's some thoughts on the new features.

Garmin eTrex Touch

Garmin has brought touchscreens to the eTrex line with the eTrex Touch 25, 25, and 35t. All three units have the same color screen, 1.43 x 2.15 inches (160x240 pixels), which is slightly smaller than the Oregon 600. The smaller screen is appropriate for the smaller size and lighter weight of the eTrex series. This is the same size screen used on the non-touch GPSMAP 64 series, by the way.

I have to be upfront here- I've never been a fan of the eTrex user interface- I've always preferred the interface on the non-touch units, such as the current 64 series. But I admit that I like the touch screen and the interface on the Oregon 600 series. In their favor, the eTrex units are the lightest trail GPS receivers from Garmin and they do everything that's essential in a trail GPS, so if you're a serious backpacker where weight is a concern, they're worth a close look.

Garmin nüvi 57 and 58 Series

This new 2015 Garmin nüvi series of street navigators feature 480 x 272 pixel, 5-inch screens and an amazing array of features for the price. As with all stand-alone navigators, these units have the maps and points-of-interest (POI) data stored in internal memory and are not dependent on a data connection, unlike a cell phone. This means you'll have navigation guidance anywhere the unit can see the sky, even in remote areas far from cell towers.

Some of the features: Garmin "Real Directions" gives spoken directions in relation to nearby landmarks, such as "turn left after the gas station." Foursquare adds millions of new POIs, and "Direct Access" guides you into parking lots and makes it easier to find a specific shop within a large shopping mall. Junction view shows you a picture of upcoming exits, with an arrow in the correct lane- really useful for multi-lane exits. School zone warnings give you advance notice of special speed limit zones and school crosswalks.

All of these nüvi's are compatible with the Garmin BC 30 Wireless Backup Camera. Up to four of these cameras can wirelessly send images to the receiver.

The 57 series includes maps and POI's of the lower 49 states, while the 58 series adds Alaska and Canada. The base 57 and 68 models have maps that can be updated by purchasing updates as desired, while LM models have free lifetime map updates, and the LMT models also have free lifetime traffic.

Garmin nüvi 67 and 68 Series

This new 2015 line of nüvi street GPS receivers have the same features as the 58 line but with a 800 x 480 pixel, 6-inch screen. The 67 series includes maps and POI's of the lower 49 states, while the 68 series adds Alaska and Canada. The LM models have free lifetime map updates, and the LMT models also have free lifetime traffic.

Garmin nüvi 3597LMTHD

If you want it all, this is the street receiver for you. The nuvi 3597LMT is the 2013 update of the 3590LMT and features a 5-inch multi-touch screen with pinch and zoom, lifetime maps of North America, customizable "dashboards", free lifetime HD digital traffic with faster updates, more secondary road traffic coverage, and no ads. Traffic information appears on the side of the display so you can still see the driving map. The 3597LMT also includes lane assist, Bluetooth, Android smartphone link, an SD card slot, voice navigation, spoken street names, landmark navigation, junction view, real time traffic, a powered magnetic mount, pedestrian navigation, and an audio book player.

Garmin nüvi 3597LMTHD 5-Inch Portable Bluetooth Vehicle GPS with Lifetime Maps and HD Traffic

Garmin GPSMAP 64 Series

Garmin GPSMAP 64

The GPSMAP 64 series is a much-anticipated update of the 62 series to include reception of the Russian GLONASS satellites. As already proven by the Garmin Oregon 600 series of touch screen trail GPS units, adding GLONASS to the US GPS satellites slightly increases the accuracy and significantly increases the reliability of the navigation fix. With more satellites to use, the Oregon 600 maintains its satellite lock under partially obscured skies, such as in canyons and heavy forest cover. Having more satellites available also makes it less likely that the accuracy of the fix will suffer from poor satellite geometry, which can happen if all the usable satellites are in a line.

Much-anticipated? Well, not all of us like touch screens for field use. Although the Oregon 600 series is vastly improved over its predecessor 400 and 500- series, I still prefer buttons while wearing gloves and in cold weather.

All of the 64-series units support additional Garmin maps, as well as custom maps. The base 64 model comes with a basemap, and 250,000 preloaded geocaches from The 64s adds an electronic compass and altimeter, and the 64st adds TOPO U.S. 100K maps.

I recommend the 64s, since there are plenty of free, high-quality maps available from as well as other sources.

Garmin 010-01199-00 GPSMAP 64 Worldwide with High-Sensitivity GPS and GLONASS Receiver

Garmin nüvi 55 and 65 Series

Garmin nuvi 55

New for 2014, the Garmin nuvi 55 series features a 5-inch screen at a very low price. The nuvi 55 gives your all the most important features- dual-orientation display, detailed maps of the 48 states plus Hawaii, lane assist, faster search, map display of nearby points of interest, speed limit, current speed, estimated arrival time, and school zone warnings.

The nuvi 56 adds maps of Alaska and Canada. The LM models feature free lifetime maps, and the LMT version have free lifetime maps plus free lifetime traffic.

The nuvi 65 and 66 models have the same features in a larger, 6-inch screen.

Garmin nüvi 55LM GPS Navigators System with Spoken Turn-By-Burn Directions, Preloaded Maps and Speed Limit Displays

Garmin nüvi 56LMT GPS Navigators System with Spoken Turn-By-Burn Directions, Preloaded Maps and Speed Limit Displays

Garmin nuvi 44 and 54 series

Garmin nuvi 54lm

The Garmin nuvi 44 series includes the essentials. This street navigator includes a 4.3-inch 272x480 pixel color touch screen, high-sensitivity receiver, maps of the U.S. and Canada, microSD card slot, spoken street names and turn-by-turn directions, lane-assist, and emergency location. If you don't want lifetime traffic or maps and are happy with a 4.3-inch screen, this unit saves you money.


Subscribe to RSS - garmin