March 12, 2016. Dallas and I stop at Red Rocks Park, off of Route 74. We park near the Trading Post, and spend a few hours view the spectacular red sandstone and shale hogbacks there. Though the area is mostly natural, a large outdoor amphitheatre and accompanying visitors center has been built on the hillside between two of the rock outcrops. Dallas views a short video and reports that many famous musicians, including The Beatles, have performed here. Meanwhile, I stand in the plaza, enjoying the afternoon sun. We then walk the Trading Post Trail that loops among the hogbacks. Both vegetation and rocks are fascinating. The area is only thinly vegetated, with bushes and solitary trees. Some of the bushes are staring to bud, though none yet has leaves. We spot several varieties of cactus and yucca growing among the rocks, as well as a small plant with holly-shaped leaves and yellow flowers. Occasional springs issue from joints in the cliffs and support lush vegetation. The rocks are a cross-bedded sandstone and shale river deposit of Pennsylvanian age called the Fountain formation. We spot many small fossil river channels. Clasts of shale, impeded in the sandstone, are surrounded with white aureoles; I suppose that they produced reducing conditions that prevented the deposition of hematite cement. The loop takes about an hour to complete.