Went on a 5-day, 1400-mile road trip all over parts of Oregon and Northern California for the first time with my buddy Shaun. We slept in the car, woke up at sunrise to photograph, and stayed up until 3 in the morning to see the Milky Way. In the end, were exhausted and badly in need of a shower, but I would do it all over again in a heartbeat.
Various state/national parks in Oregon and California. July 2016. (Instagram)
The lava tubes people see most, and occasionally tour, are created by flowing lava (http://tmblr.co/Zyv2Js1YY_xmG ). The lava cools most rapidly at the top, causing a crust to form that stands up even if the lava flow ends. This is a different type of lava tube.
This lava tube is found alongside the Coso Volcanic Field in California and it was created by erosion. Water flowing over rapids and waterfalls formed eddies that stayed in the same spot and cut downwards. This entire cave is a vertical tube with an almost rifle-style pattern left on the walls. No scale is given but it’s probably less than a meter across.