Robert G. asks:
I have a client who is interested in providing their trail network for users to download to their handheld GPS receivers. After searching extensively, I have not been able to find a solution to what I thought would be a simple process: How to convert existing GIS data into a format that can be downloaded onto any GPS receiver, without having to convert the data each time. Ideally, the file would be converted once (or at least once per receiver manufacturer), and provided for download via their web site.

GPX, the GPS Exchange Format, has become the de-facto standard for delivering GPS and GIS data to consumer-grade GPS receivers. GPX files can be used by hundreds of GPS receivers and mapping programs, including ExpertGPS, Google Earth, MapSource, MapSend, and MapCreate. Ten years ago, there simply wasn't a common file format, so you had to distribute different files for each brand of GPS receiver (and usually, several different formats for the GPS receivers within a single brand). GPX has changed all of that.

I happen to be one of the founding fathers of the GPX file format - I helped write the initial GPX 1.0 file format, and have written and maintained the GPX documentation since day 1. ExpertGPS, as you might expect, uses GPX as its native file format, and is widely used as a GPX authoring tool and GPX file converter.

Converting GIS shapefile data to GPX

Once you configure ExpertGPS to use the same coordinate format and datum as ArcMap, you just click Import on the File menu, and select your shapefile data. ExpertGPS Pro will convert your .shp polylines and points into GPS tracks and waypoints. Click Save to save the trail network in GPX format. Your data is ready to be distributed - anyone who downloads the GPX file from your Web site can send it to their GPS using their favorite mapping software. (If they don't have software, EasyGPS is GPS freeware that works with any GPS.

Michael B. from Washington asks:
I'm interested in using my GPS for hiking and I found the Backpacker.com web-site has hikes with trail routes that I can export to ExpertGPS. I was hoping that there were other such sites you can recommend that have a more complete list of hikes/maps.

Recommended sites with GPS trail data in GPX format

There are lots of great Web sites for exchanging and downloading GPS data. ExpertGPS uses GPX, the GPS Exchange Format, as its native file format, so you can open GPS data from hundreds of Web sites, print out a map, and send waypoints, routes, and tracks directly to your GPS. Here are some of my favorite sites that support the GPX standard:

TravelByGPS.com - Doug Adomatis runs a great site with lots of hand-collected GPS waypoints and tracks. Each data set has a detailed description, unlike lots of the sites which claim to have 100,000 trails. (They do, but all but a handful are just dumped out of a GIS database with absolutely no information accompanying them)

GPXchange.com - Hans Wain and Fred Williams have a site with lots of trail data, and offer a convenient way to print out really nice poster-size topo maps and aerial photos with your GPX data on top.

EveryTrail.com - A newer site with lots of GPX data.

MapMyFitness.com - Runners can share routes or download and view them in ExpertGPS.

GPX Resources at TopoGrafix.com - At the bottom of the page you'll find additional Web pages that offer data in GPX format.

Know a good, free site that allows public download of GPX data? Add a comment below!

Many organizations and GPS hobbyists are looking to combine GPS tracklog data with GIS layers (contour lines, road centerlines, and boundary data) and create professional-quality maps. The styling features in ExpertGPS allow you to create some nice-looking maps, but sometimes you need to step up to a true graphics package like Adobe's Illustrator.

Up until now, it's been difficult to take your GPS data and import it into Adobe Illustrator. With the upcoming support for SVG export in ExpertGPS, you'll be able to take any GPX file and output it as Scalable Vector Graphics, which you can then import right into Illustrator. The image above shows the output from ExpertGPS in Illustrator: the topo map layer is on the bottom, and above that are layers showing the town boundary, all of the ponds and streams in the area, all of the major roads, and finally at the top, three GPS tracklogs I recorded around town.

I originally started implementing SVG support in ExpertGPS several years ago, but there wasn't much use for it at the time. Now that more browsers (Firefox, Safari) natively support SVG, and more people have the Adobe SVG Viewer for Internet Explorer, it's a more useful export format.

If you're involved in mapmaking using Illustrator or another vector graphics program and would like to help with the design of the "GPX to SVG to .ai" workflow in ExpertGPS Pro, or if you have other workflows you'd like to see ExpertGPS handle, please drop me a line.