I felt like a zombie when my alarm went off this morning - all red eyes. Last night, my face had been red and yellow where the cold had got it but the damage wasn't permanent. I checked my door - hanging from it was a red and gold bag. This time Pottaskefill, Pot-Licker, had visited and left me a gingerbread troll and tree. At least, I assume it's gingerbread. I haven't eaten it yet.

I put on my warmest clothes and brought more with me, made some rolls (I bought rolls yesterday and brought cheese with me) and went to await my pickup. For some lunatic reason, they came to the back door. No time at the terminal to go to the cashpoint, I was straight on the bus which then took forever to depart and sat for five minutes halfway out of the bus park.

We drove an hour and quarter south east along the Ringroad before our first stop at Hvolsvollur. I am still the only member of the group who's realised it doesn't take twenty minutes to cross the road to get real food at the supermarket rather than buy one of the small selection of sandwiches and a cup of coffee at the petrol station. Three people had burgers and chips, actually. How do you eat that in twenty minutes? I also waded through the snow to Landsbankinn for some cash at long last and then didn't get a basket at the supermarket and finished up dropping biscuits everywhere.

We drove onwards. The six of us snowmobiling were dropped off at the Solheimsjökull to be put in a new truck and taken to the glacier while everyone else went off for an ice hike.

At the Arcanium hut we were given fat fluffy boilersuit things, balaclavas (it touched my neck. I really didn't want to wear the balaclava) and helmets. My gloves were deemed satisfactory. Now there were twelve of us - the other six having arrived independently - we squeezed into the truck and drove up the mountain. I had no idea such a thing was possible.

We all remember my old friend Eyjafjalljökull (hereon in called E16, my favourite nickname for it), the volcano that erupted in 2010 and caused air traffic chaos. E16 is next door to Mýrdalsjökull where we were snowboarding and Mýrdalsjökull hides another volcano, Katla. Katla is ten times as big as E16, ten times as powerful and she's overdue an eruption. Last blew in 1918 and goes off every 70-100 years. Air traffic will be closed for months when Katla erupts. I was snowmobiling right on the edge of her 10km wide caldera.

At the top station, we were given our snowmobiles. I was sharing with a French girl called Laura and she volunteered me to drive first. They're easy enough to control - squeeze the trigger with your right hand to move, squeeze the brake with your left to stop. Don't do both at the same time. But they're scary - very noisy, very smelly and they feel like they're going to tip over. I nearly did tip it over. We all went along in a line, following Þórr, our guide. There was fresh snow and potentially crevasses invisible underneath it. At one point I went off the tracks and the thing tilted alarmingly. It took a lot of effort to pull it right and get it back on the tracks. My arms were aching from the effort of steering it and holding the throttle but gradually I learnt not to hang onto it but just to ride it and use the handlebars to control it. We picked up speed. I was still nervous taking bends and going downhill but straight uphill and in a straight line was starting to be fun. Cold but fun. As we got higher and higher, something seemed to be wrong with the visibility. I could hardly see the snowmobile in front of me but I couldn't work out why. It wasn't until we stopped at the top that I discovered I was breathing and steaming up my sunglasses. It was cold and windy at the top. The wind was blowing lots of fine powder onto us, the only way I could survive was by pulling my balaclava right up over my nose which just steamed my glasses up more. Þórr built a model of the glacier and Katla in the snow and explained what will happen when it erupts and then we took photos, swapped drivers and went back down.

I thought driving a snowmobile is scary. It's even scarier being a passenger. I didn't whimper much but I did think we were going over and I thought we were too close to the one in front a few times. It didn't help that even though I'd cleaned my glasses, they still kept steaming up and I was flying along on an overgrown lawnmower almost completely blind and with the right side of my face being frozen off. As we went lower, the wind dropped. I managed to get my glasses clear in time to enjoy the fun and games of riding an unstable snowmobile through a snowfield covering pointy lava rocks which we kept hitting. And then the snowmobile in front of us capsized. It didn't seem to do any harm - I guess the skis, the boards and the handlebars hold its weight up and stop any of it actually landing on the passengers. Þórr got it upright and we carried on - less than five minutes from home. We could see E16 now the cloud had gone and as far out at the Westman Islands, which were covered in snow too. The snowmobiles were packed away into their containers and then we went back down the mountain to take off the warm clothes, eat our lunch and be taken back to meet the main group at Skogar.

We had nearly an hour at Skogar Folk Museum. It's interesting in places but mostly it's just a collection of stuff. Old chairs from people's houses, old farming tools, some very old books, fishing stuff - some gems but largely old junk. The whale vertebrae carved into buckets and stools etc are interesting, and the brass ring from a mythical chest of treasure hidden under the waterfall. There's a collection of stuffed birds downstairs which is starting to look a bit old and moth-eaten. I'm not a huge fan of Skogasafn.

Skogafoss, on the other hand, looks amazing in the snow. I've seen it in summer when it's green and autumn when it's orange and winter when it's cold and grey but today it was glorious sunshine and blue sky at Skogafoss and it looked lovely. The Nicaraguan boys offered to take a photo of me with it and I agreed, even though I have plenty of photos of me at this waterfall.

Our last stop was Seljalandsfoss, which is lovely but it was dark and the floodlights weren't doing enough to make it show up on camera. It was also freezing cold and I was tired and just wanted to go home.

An hour and a half back to Reykjavik, not stopping at Hvolsvollur this time. Another half an hour dropping off. I was last because my hotel is closest to the BSI terminal. I had a shower - my hair has been in plaits for two days and was still slightly damp from the two spas yesterday and was properly poodly when I undid the plaits. And I ate just about everything I have. A trip to Reykjavik might be in order on the way home tomorrow.