Inteneresting about the ways to occupy the mind...I have some training in geology, and find it useful to read or carry a guide to the roadside geology of a mountainous area I'm touring through. Then, when climbing a long pass, one can look and try and figure out which rock formations are exposed in the road cuts. Examples when crossing the Sierra from west to east along highway 4 would be the Tertiary Ione sediments along the ancient shoreline, the Table Mountain inverted lava flow, the ancient suture zone along the Mother Lode belt that led to the gold mineral veins along the subduction zone, the relatively young Cascade-Arc-type volcanics that sit atop the much older Sierran granites, and the abundant hydrothermal veins that cut both granites and volcanics near the range crest and on the eastern side, leading to silver mines.