From now on, we will assume that you are using SRTM-3 data. Unless otherwise noted, the process for SRTM-1 is identical.
Create a new folder in your <tt>TerraGearWork/Data/</tt> folder called <tt>SRTM-30/</tt>. Now download appropriate data from ftp://e0srp01u.ecs.nasa.gov/srtm. You want ALL .hgt.zip files covering the area you want to create. Depending on the size of your scenery, there may be quite a few. The reason why the directories are called SRTM-30 is because genapts (a tool we will meet further on) will look for a few known,
hardcoded directories in it’s working directory. SRTM-30 is one of them and this is the least confusing in that list.
Unzip all of the .hgt.zip files using your favorite software.