... /GPX/1 /1/ Here's one of mine, opened in *Notepad++ 2_120500_590000000.png trkpt is a single track point, and you can see it's easy to extract the latitude and longitude figures. I can post a bit of code showing how to do that if you wish? Converting the lat and lon to X,Y co-ordinates for plotting on a screen map at different zoom levels is the tricky bit, involving some maths. You can enter lat and lon directly in OSM to find the map location: 2_120511_430000000.png Note that for most of the UK, longitude is negative. To get some GPX files to play with, click the GPS Traces link above. *Notepad++ is the essential (free) text editor for programmers: http://notepad-plus-plus.org/ cheers, Martin. posted: 12 Dec 2020 16:36 from: DerekStuart Hello Martin, thank you for the info. If I've understood the process correctly:- I use a GPS device, which I instruct where to output its data- Say ...