Occasional Hyker: Creating Custom Topographic Maps for your Hand Held GPS Unit

Creating Custom Topographic Maps

for your Hand Held GPS Unit - Part 1

A Brief Introduction

So you just bought yourself that hand held GPS unit that you've been wanting. It looked so good in the store and it came in a very nice box with impressive and professional looking graphics on the outside. You, of course, pay little mind to the box as you open it up and extract your new toy. A mapping GPS unit! Now you have the power to always know just exactly where you are at all times and it fits into the palm of your hand!! Hurriedly you turn the unit on only to discover... the damn thing doesn't have hardly any detail on the base map. Now what?

Shiny and at the moment, useless.

Well Garmin is hoping that you will purchase map packs from them. I guess it is good for Garmin, I mean, when you buy the map packs from them you end up spending half again what the unit cost just to make it... well, usable. But what if I told you that you could create accurate, custom maps for your Garmin GPS unit and all it will cost you is some of your free time? Sounds great doesn't it? Well continue reading after the jump to learn how to create your very own completely customized maps for your GPS unit.

I have found several different tutorials on the web for creating custom maps for your Garmin, but most of them were either not complete, vague, or they used software that I did not like. I am going to lay out, in a series of blog posts this week, a "How-To Guide" for downloading USGS data and creating custom maps for your Garmin GPS unit.

Here are the basic steps that we will take:

Obtain the necessary FREE software.
Find and download the map data that you need.
Process the map data. (For topography only)
Create the map.
Convert the map to a Garmin Compatible format.
Load your map file into MapSource
Use MapSource to upload your maps to your GPS Unit

This task takes some moderate computer know how, but I will try to walk you through it in a simple step by step fashion. Let's start with step number one: Obtain the necessary FREE software. (I keep emphasizing free because there are many good people out there who have spent time and energy creating these software packages for our benefit. While they do not charge for use of their software, please consider donating to them. Hobbyist programmers need to eat too.) We will need several tools in order to process our data and assemble it into a map. Download and install the following:

FWTools - Download Here
GPSMapEdit - Download Here
cGPSMapper - Download Here
MapSetToolKit v1.40 - Download Here

I'll briefly explain each program:

FWTools is the program that we will use to produce topographical maps for our GPS units. FWTools allows you to process contour data downloaded from the USGS into elevation lines. In it's raw format, the USGS data (called GeoTiff files) look like satellite pictures which indicate elevation using shading. With FWTools we will run a shell environment in which we use the GDAL commands to interpret the elevations in the GeoTiff files and produce shape files with topographic contour lines. (Note: This step is processor intensive and may require a large amount of time to complete.)

FWTools is an installable program. Download the Windows 32bit installer and run to install. After installation there will be a new program group in your Start -> All Programs menu called FWTools. To use FWTools select the FWTools Shell icon.

GPSMapEdit allows you to assemble your map data into one file. We will use GPSMapEdit to bring our shape files together, layer them and also filter them as required. I'll explain more about layering and filtering when we get there.

GPSMapEdit downloads as a .zip file and does not need to be installed. Simply un-zip the program (I would recommend un-zipping it to your C Drive) and double click on the MapEdit.exe program to use.

cGPSMapper is a support program used by GPSMapEdit to create Garmin compatible maps. You don't actually use this program yourself.

cGPSMapper is also a .zip file that does not require installation. Again, un-zip to the C Drive.

MapSetToolKit enables you to install your new map file into MapSource.

MapSetToolKit is a... you guessed it, a .zip file. Once more, un-zip to the C Drive.

Stay tuned. In my next post I will be discussing finding and downloading free data that we will use to create your maps!

~Occasional Hyker