I don't know how it started. Maybe it was an urge to document events/locations/time/trips. I dunno. I started taking photographs of rental cars on every trip that included driving. Here's another example commemorating that tradition. As I was driving across the Plain of St. Agustin just west of Socorro, NM, I was so taken with the beauty of all of the stratocumulus clouds, rain, and the shadows I had to stop and take a moment to be out in it and experience the vastness of the scenery. As you can see by the hood and windshield, it started to rain so I had to retreat back into the car. The area is very sparsely inhabited. It looks like you could walk/drive across it in a shorter time that it actually takes.