We climbed the road. Árni's GPS told us how high we were going, and before too long we were 700m above sea level, and there was snow on the ground around us. Rocky ground covered in snow eventually gave way to the glacier proper. We stopped to reduce the tyre pressure still further, and then drove onto the ice. The wisdom of driving in a convoy became clear here; sometimes a vehicle would get into some difficulties up the steeper slopes, and anyone driving alone would have been pretty miserable. The other convoy members were ready to help, but the odd slippery moment was not a big problem, and we all climbed up and up and up.
It was getting dark and progress was getting slow. The problem was that there had been heavy rain up here. Snow would have been fine, but the rain had frozen and the driving conditions were far more treacherous than they had been a few days earlier. The jeep rocked wildly as we reached 1000m above sea level. Árni was a policeman by trade but had also driven jeeps in Afghanistan. His skills here were impressive and we rocked and bounced our way up the glacier, eventually reaching 1400m above sea level before heading down into the pass. We'd left Reykjavík at 4pm, and we'd hoped to reach the volcano by 8pm, but the journey continued. By 9pm the daylight was fading fast, and suddenly in the distance there was a vivid orange glow. Our luck was in.