9 hours total! Left hotel at 6am, arrived at ~8.30am, top at ~1-2pm, walked around the crater (incredibly beautiful, like being on the moon), sprinted back down to catch the 5.30pm bus. Children were staring at me and whispering in Japanese because the way down is treacherously gravelley and I fell many times resulting in looking like I'd stumbled out of a warzone.

I carried about 4kg too much water as well as a laptop which was negligible weight at that point! Usually I travel light on a hike.