It's now Wednesday morning and I'm finally starting to write Monday's blog. I won't get it finished before I have to go out so it'll be Wednesday night before it's done. I'm hoping to be back by six at the absolute latest tonight.

So, Monday. Pickup at seven. There was a Japanese girl from a few doors up also going on the same trip and when the minibus hadn't arrived by 7.15, she decided it would be best to walk down to the office. A few minutes later, I decided to do the same thing. It's actually only five or ten minutes there.

When I exchanged my piece of paper for a ticket, the nice lady looked at me in confusion and asked if I got picked up and when I said no, I'd walked, she radioed the bus driver to tell him I was at the office, so the bus hadn't forgotten, it was just later than usual.

The bus we were getting on was the Skaftafell Express, taking four tours to the same starting point and it was a minibus. A minibus, as it happens, is not my favourite transport for travelling five hours, especially when someone is quietly and discretely sick a couple of rows back, my seatbelt isn't working and I'm sitting in a single seat on one side with my bag under my feet. For five hours. For once there was no commentary - we had a driver, not a driver-guide, who didn't speak very much English and looked a lot like Martin Freeman.

We drove without stopping for two and a half hours before making a ten minute stop at Vik, then we were off again and having left at 7.30, we reached Skaftafell National Park at around half past twelve. We'd come down past Hveragerði, through Selfoss, past the turning for Hekla, past Seljalandsfoss and into new uncharted territory, which followed the south coast past Mýrdalsjökull and on towards Vatnajökull, the biggest glacier in Iceland. Glaciers cover 11% of Iceland's surface and this one is probably bigger than all the others put together. It's apparently - like so many other big things - about the size of Wales.

We were taken to check in with Glacier Guides, who then took us over to the visitor centre for lunch - Icelandic meat soup and a sandwich. I'd brought food so I went and sat outside and ate it and was back at the meeting point half an hour later as instructed. We were fitted with crampons and given ice axes and then when everyone was kitted up we got in Glacier Guides' yellow American schoolbus. They have three of them, bought from eBay, which they use for ferrying their customers around. We drove fifteen minutes around the bottom of the mountain to Fallsjökull - the Falling Glacier, which is a massive icefall.

First there was a surprisingly hard hike over what looked like lava and dirt but what was actually glacier ice covered in the assorted filth it had picked up on its journey down the mountain. I had put on all my warm layers and got far too hot by the time we got to the ice. The coat came off. Then we had to stop to be taught how to put the crampons on - reasonably easy but I couldn't seem to sort out the stopper knot for tying up the foot or so of loose strap. By the time we were all standing in our crampons and posing for photos, it had gone cold again. The coat had to come out again. Then we were onto the glacier.

The crampons didn't feel as secure as I'd been expecting and the first time I had stamp a foot into the ice and use it to drag myself up was a little bit terrifying. But it held and after that it wasn't so steep.

Our first stop was at a cauldron, which is a hole in the glacier where the water swirls down. This was a small one but Snorri, our guide, showed us how to approach so we didn't fall down it. Then we hiked upwards. The ice was mostly covered in a fine coating of blackish ash but in between, you could see that it was really blue and transparent for miles down. Snorri said the ice is about fifty metres thick but obviously, you can't actually see that far.

Next stop was at a river of absolutely pure clean glacier water. Snorri dug his ice axe into the banks to use as a bar, then you had to dig your feet into the sides, hold onto the axe and lower yourself over the river to lap from the water. Or, if you weren't that brave, he also had a collapsible cup to gather water from the spring that fed into the river. I was that brave but not strong enough and finished up with my knees in the water.

We carried on upwards once everyone had finished playing with the water, up to a super-cauldron. We were only allowed to see this one at a time, with Snorri holding onto us from a couple of feet back as we leaned over to see a very deep, very blue hole in the ice. When we'd all had a look and taken a photo, Snorri found a boulder about twice the size of my head and heaved it down the hole. First there was a pause, then a splash, then a lot of booming as it fell down this hole for further than we could imagine. No, you definitely didn't want to fall down that cauldron. We hiked across the glacier to where the cleanish ice met the dirty ice. This didn't look very impressive but on the other side, there was a vast bright blue ice cave carved out of it, the perfect spot for photos. We weren't allowed to get too close in case the thin ceiling collapsed and dropped half a ton of ice on us but we got as close as we dared and took lots of pictures.

Then it was back up onto the clean ice and time to trek back down to the start point, or at least, back to the patch of dirt where we'd started. Crampons came off and we were asked to please "go crampon-fishing" before we left - hold the things by the long straps and dip them in the water a few times to get the mud and dirt off them.

The hike back over the dirty ice seemed longer. Part of the path had that very morning disappeared under a rockfall so an hour before he picked us up, Snorri was out there with his axe building a new one. He uncovered a patch of ice for us and cleaned it off with some water so we could see that under all the dirt and soil and ash, there really was crystal-clear ice underneath.

Back at the schoolbus - actually a different bus, one of the guides had swapped it while we were on the glacier (the first one had a "Body Fluid Clean-up Kit" up at the front and the second only a First Aid Kit) - we all stripped off cold wet clothes and settled down for a forty-five minute drive round to Jökulsárlón. There weren't many of us - a Japanese couple and an Austrian woman, none of whom spoke very good English. An American and a Canadian who'd met at college and were now at dental school together, a Ukrainian girl who'd been living in Iceland for a year, Perla who works for Iceland Excursions but was doing this trip (for free!) because it was her day off and she'd never done it and a Swiss boy on his way back from a gap year. In Ukraine it's very rude to ask how old someone is, so we didn't get Lena's age out of her but Perla is twenty-three and the Swiss boy twenty-two so I very suddenly began to feel like the old lady of the group.

Jökulsárlón is a stunning place. It's a lagoon, only about fifty years old, where the glacier meets the sea and pieces of ice break off to float around. Some of them get stuck on the bottom, which is why they don't drift past the bridge and out to sea and then the others get caught up with them. Occasionally they flip over, even the massive house-sized ones and they do it really quickly, in about a minute and a half. We were delivered to the jetty of the landboat - it looks like a boat but it has wheels and it trundles over to a plank and you walk on and put on a lifejacket - that looks ridiculous when you're already wearing all the clothes you own and it means you can't move very easily.

We had to stay sitting down as we trundled over to the edge of the water, then we drove in, the wheels came off the bottom and we were afloat. We spent about forty minutes sailing around the lagoon, seal-watching, looking at huge blue icebergs and massive blue, white and black striped icebergs and being entertained by lunch for one boat driver being delivered by another via the men in little black rubber boats - these were used in Vietnam and the one with stripes on apparently still has bullet holes in it. They're not always used for food deliveries - they tow the smaller icebergs around to clear paths for the landboats. They also deliver chunks of ice. One of them delivered a chunk of crystal clear ice to our guide, a piece of ice the size of my head but much lumpier. We got a lecture on the formation of glaciers and the reason ice looks blue or clear and why this huge chunk was so much clearer than normal ice and then he broke it up with a hammer and handed out bite-sized pieces of thousand-year-old ice from the bottom of the glacier for us to eat - the oldest thing we'd ever eaten. It didn't taste brilliant. Mostly just of ice. But I didn't finish mine because ice is quite slippery, especially if you're wearing gloves and mine escaped before I'd had more than a couple of nibbles. I probably wasn't helping my grip by taking photos of it, admittedly.

Back on dry land we went for waffles, served warm and filled with an unidentifiable but tasty jam and served with a lot of cream. I didn't eat the cream and I was also much slower than everyone else - when they all left, I had to pick up the remains of my waffle and take it with me. We had a couple of minutes for photos of the lagoon while Snorri went to fetch the schoolbus and Lena used that to go for a dip in the ice-cold water. That meant she was a bit late getting back to the bus but Snorri used the time to entertain himself and us by opening and closing the door and making the Stop sign pop in and out.

It was about an hour back to Skaftafell, into the minibus and then we were heading back. It was quicker this time - I clockwatched most of the time. An hour and a half to Vik, then I lost track a bit, ten minutes Selfoss to Hveragerði, forty-ish minutes from there to Reykjavik. A grand total of approximately exactly four hours, with a brief stop at Hvolsvöllur. Quite where the extra hour came from on the way, I have no idea. We got back at about quarter to eleven, having left at half past six. And it was still daylight. The sun was setting but it was definitely still visible and the sky was still bright - the weather improved on the way home.