Half way up, just about where the lowest snow remained, I realised what a task I had undertaken. The ground was soft and composed of loose rocks which made traction difficult; the slope was steep and I spent half the time on all fours scrambling up; and I wasn't making good time. I had departed for the summit 10 minutes earlier than the recommended latest departure time of 9:15am, but the pace was too slow. I estimated that I would need another 5 hours to complete the crossing once I returned to the base of the volcano, which meant being down there at 11:30am to be back for 4:30pm and the last bus back. I was in a sticky situation.