One of my own pictures for a change. This is Hvannadalshnúkur, at 2111m it is Iceland’s highest peak. The picture is of my camp there while skiing around the summit caldera.
The peak sits on the brim of the Öræfajökull glacier, part of Europe’s largest glacier Vatnajökull. A huge volcanic caldera filled up with glacier ice. The volcano is actually one of the most powerful active volcanoes in the world. Luckily it is not too active though. There have been only two eruptions in it since Iceland was settled, in 1362 and 1727. The most recent one was not too serious, thought to have killed two people. But the one in 1362 is perhaps the most devastating eruption Icelanders have experienced, competing with the Laki eruption in 1783 (tough century…). It killed everybody in a very large surrounding area and left what had been a prosperous farming area, uninhabitable for decades. The output of ash was over 10 cubic kilometers, at least ten times greater than from the famous Eyjafjallajökull eruption last year. However the ash was not the only danger. The major problem was water. When an eruption occurs under glacier ice, the volcano must melt through the ice, causing massive flash floods.
What people therefor most likely experienced was something like this. Massive earthquakes that caused houses and shelters to collapse. This was followed by a powerful rumble from the mountains, strong sulfur smell from the rivers (like rotten eggs) and a glimpse of glowing lava up on the peaks. The distant red glow would soon disappear as the black cloud of ash covered the farms and glowing rocks up to a meter in diameter rained on the lowlands. Visibility would have been limited to only a few meters when the massive flash floods of glacial melt-water, icebergs and volcanic mud came charging down the valleys. This would have been the last thing these poor souls experienced before being washed away or blanketed under meters of ash. It was said that there was only one survivor in the whole Litla Hérað (E. Little Shire) area, later named Öræfi (E. Wasteland).
Quite a wonderful feeling to sleep on top of such lurking power :)