is a volcanic fissure and a fault in the eastern Myvatnsoraefi area.
It is 2-3 km wide; its walls are 10-15 km long and 20-40 m high.
It is easily traceable all the way south to the central volcano
Dyngjufjoll (Askja), and north across the Holssandur area, where the
summer road passes through its crater row near the waterfalls
Hafragilsfoss and Dettifoss.
At Hafragilsfoss it is possible to observe the cross section of
one of the craters in the western wall of the canyon.
The western crater row is older and its northern part is called
Sveinar and the southern part Rauduborgir.
Altogether this volcanic fissure and fault line is 70-80 km
(42-46 miles) long and it is roughly dated 8,000 years back.
of the eruptions have created Pa Hoj Hoj lava fields and along it, near
road no. 1, is one of the youngest crater row of the country, which
erupted at the
same time as the major eruption of the Dyngjufjoll central
volcano created the explosion crater Viti and Lake
Oskjuvatn, the deepest of the country.
The fissure eruption near the main road started in February and
came to an end in April and created the so-called Nyjahraun lava field
clearly visible from the road.
another eruption took place within the same eruptive system between
Dyngjufjoll and Nyjahraun, i.e. just east of the shield volcano
Never before in the history of volcanism in Iceland had witnesses
to eruptions describe them on paper.
The naturalist Thorvaldur Thoroddsen witnessed the fissure
eruptions and the Englishman William Lord Watts, who made the first
recorded crossing of the ice cap Vatnajokull at the same time, witnessed
the Askja eruption.