I got an garmin etrex20 and was wondering if i have to buy maps or if i show up to the mountain will it have the trail preloaded?

I personally would take a paper map and compass anyway. GPS units do get damaged and their batteries run out.

The best place to start is by reading the manual. It either came with a printed or electronic manual. When you have read that, then ask specific questions. You are asking others to do your work for you with "how far is up?" type questions.

There are classes at REI....

There are also free maps online if you don't want to buy a set for the GPS. Search the forum, this is a oft discussed topic.

Not to be critical, but if you don't know what to do with your GPS, why did you buy it?

For the how to use it part, read the manual. The Etrex 20 comes with a very low resolution US map loaded; it isn't much help. You can download USGS 15' sheets for the various states from the web but first you should learn to use the thing. There is a detailed downloadable manual on the Garmin website; a good place to start. There are several sites that offer downloadable freeware maps. Use Google to find them. You'll need to buy a micro SD chip to store maps if you want detailed coverage; Garmin will happily sell you these chips with detailed maps preloaded for $50 to $100 apiece.

I bought an Etrex 20 to use for mapping. In my opinion it is dead weight for most trail use and not much more useful off trail except in bad weather on featureless terrain. If one can't stay located on trails without a GPS then perhaps one should stay home. Not everyone agrees with me on this though .

You'll have to start with a map and compass class. Then a GPS class.

Trying to use a GPS for navigation without this knowledge can end in search and rescue... just FYI. Nine times out of ten I rely on the paper map as I find it takes less time than scrolling around that tiny screen.

You can get free maps at http://www.gpsfiledepot.com. They've got Topo, trails, public land, and many other great maps.

You can use Garmin's "Mapsource" or "Basecamp" software to load the maps you need for a specific trip. I use a Mac so I have to use the Basecamp software, but it's pretty good and they're both free. You can find those apps on Garmin's web site.

As others have said, reading the manual is the place to start. When I got my first GPS I played with it a lot before I used it for backpacking, and the first few trips I used it on were on familiar ground. I tested the "Track" and Track Back" features and setting waypoints to see how accurate they were so I knew what to expect, and played with all the features.

I found that I could easily lose a signal in steep canyons and thick forests. Your eTrex is better than my old eMap, but that can still happen to you, so you need to find those limits and be prepared to work around them.

I also found that at its best it could be very accurate in showing me my track and pointing which way to get where I wanted to go, or not at all accurate, so it took a bit of practice to really make good use of the info it provides.

My first GPS came with a "Quick Start Guide", and I carried that with me for a long time (more than a year) while learning how to use it. Your's probably has one too, but you may have to print it out yourself. I strongly recommend you do that. The menus on the eTrex can be confusing, at least at first, and you need to learn how to get to the info you'll use most. The Quick Start Guide will save you hours of frustration trying to find what you're looking for.

As others have also said already, bring a printed map and compass too, and use the GPS to locate yourself on the printed map, and use the printed map to give you the bigger picture. With the tiny screen on those handhelds you can lose your point of reference pretty fast when you zoom in or out very far.

Never put yourself in a position where you must depend on the GPS to get where you need to go, they can and do fail. I've bought three Garmin GPS units over the past 10 years or so and two of them died with no warning or reason.

All that said, that is a pretty capable GPS with some great features and the more you know about using them the more you can learn about navigating without one. They are a great learning tool if you use them for that purpose. Used correctly you can hone you map skills and locate some great spots that might otherwise be hard to find, and find the shortest route when you need or want to. But there's also a lot of other info they provide, like Sun and Moon rise and set times, solunar tables for fishing, hunting, or just viewing wildlife, locating water sources like springs and creeks, finding distance traveled and average miles per hour. Plus, it's a lot of fun to upload your GPS trip data into your Mapsource or Basecamp software when you get back from a trip and review your track.

I think the eTrex models are a great starting point for learning to use a GPS. I liked my old eMap better because it had a bigger screen and a simpler menu, and I really like the "Oregon 200" model I have now, but the eTrex is a good choice to start off with. The software isn't as easy to use as I'd prefer, but it has a lot of features so you can learn a lot from it.

jrm788,

I have a Garmin as well. No, mine at least came without maps (and I live in Canada, so prepackaged maps would be unlikely to do me much good). I have learned, over several years, to be fairly proficient with it, but I generally just use it for finding lost and abandoned trails for which I have maps.

For actual on-trail backpacking, I very rarely (like once) actually carry it. Maybe it's just habit, but I find paper maps (and occasionally compass) quicker and easier to use.

If I'm ever able to get back on the trail in any serious way, I think I'll try one of the apps for my cellphone GPS (that daughters and wife now insist I carry). I also use it for camera, weather, time, etc.

best, jcp