Fascinating looking at the valleys across the Sahara, and imagining rivers once running through them.<p>There's some fascinating fuel for imagination when you focus on the Sahara, and some very surprising features and remnants of life hanging on. The best example is Siwa, which is an utterly magical place to visit, and feels like a real edge of civiliation.<p>Climate change is always spoken about with negativity in the mainstream narrative. However, I always wondered whether more heat = more evaporation = more rain = more life; bringing regions like the Sahara (and periphery regions like the Sahel) back to life .<p>Makes you wonder whether - in an alternate timeline - if a Mongol messenger hadn't been backstabbed, Baghdad hadn't been sacked, and the Islamic world went on to become today's centre of science, finance, development, etc, wohether our current perception of climate change would be seen as a global positive and catalyst for life?