Forest fires are very uncommon in Iceland for two reasons. The first reason is that Iceland is pretty wet so the ground is pretty much soaked a lot...
The second reason is that there are no trees. What happens however every spring is that some nutter (usually immature teenagers) decides to torch the dry grass. Usually the outcome is a small burnt patch like the one below. However just a week or so ago a huge area close to Borgarnes (remember the picture of the coke can? ) burnt because somebody decided to toss a cigarette out the window of their car. Over 67 square KM gone. Luckily the farms and farmers of the area survived.
NASA recorded this on their satellite

photo from
Iceland's meteorological office website
these are on the ground
- The Thor
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