Where is the sun? Which direction is the sun traveling. What time is it. Where is North in relation to the sun. What cities are around me? What do the road signs say.
I rode for 40 miles using this method on Wednesday and I had absolutely 0 regrets of the route I traveled. I also found amazingly beautiful roads I would never travel on because I did not use my Garmin's GPS function or a pre-made map.
When I want to log serious data of lap times or need to navigate on a pre-made route for a group ride I'll enter a map. Otherwise, speed, cadence, power, time, heart rate, distance traveled and elevation climbed is what I like know while riding. I like to look at foliage, landscapes, and clouds when I ride.