GPS

Caspar and I walked a 16km (or 10mi, if you are not familiar with metres yet) tour in the Odenwald. Mainly through forest. Only twice uphill, a total of 450m, so not bad.
I had prepared myself with a planned tour. I usually do that, so I know I won't exaggerate :). I do have a smartphone, with GPS, so I could use that to find my path. But for longer tours, especially when I am not in known terrain, I prefer my GPS handheld. After my start with a PDA with GPS (I used that in my car too), I had one of the first of the Garmin GPSmap devices and now have this one. I like the preciseness (1.8m), amongst other features. With a good map installed you should be able to find your position on the map.