For those going from Reykjavík to Akureyri or reversed a great option to the main road is Kjölur, the road through the Highlands, passing the hot spring oasis Hveravellir. This is a real pearl between the big glaciers Langjökull and Hofsjökull. Here there are a lot of interesting hot springs to look at, including a geyser. It is also possible to bath in the water from the springs. During the summer there are daily bus trips between Reykjavík and Akureyri, through Kjölur. Making shorter stops at Gullfoss/Geysir and Hveravellir.
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Eldgjá (Fire canyon) east of Landmannalaugar is a long, wide and green canyon. In some places it's as wide as 600m and 200m deep. The most scenic attraction is Ófærufoss, a large waterfall in two steps. There used to be a natural bridge over the lower falls, wide enough to walk over, but it collapsed a few of years ago. Eldgjá can be reached by 4wd cars, but there are some rivers that have to be crossed. It's easier to take the bus on the route: Reykjavík-Landmannalaugar-Skaftafell.
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For those who want to visit a volcano, Askja is definately one of the best options. As for most highland attraction a 4wd car is needed if you want to get there. In summer there are also day tours to Askja from Lake Mývatn. On the way to the volcano you will pass a few other interesting places, among others Herdubreiðarlindur. This is a green oasis in this otherwise black sand and lava landscape. Here is also Mount Herdubreið, often called the Queen of Icelandic mountains. The mountain is very impressive (1682m) and was formed during a volcnic eruption when all of Iceland was covered with Ice.
Drekagil (Dragon's Canyon) is a very impressive, but fairly narrow, canyon right next to Askja. It is possible to walk at the bottom of the canyon, but it is difficult because of the river running there, so be careful.
In early summer there is usually a lot of snow up here and tour buses don't operate until July. Even then there can be much snow left and you might have to walk for hours on snow to get to the volcano itself. If going with Mývatn Tours though you will be travelling part of the way with a snow-mobile.
One of the most spectacular things about this trip is that it is possible to take a bath in the explosion crater Víti next to the main crater, so you might want to bring your swim suit. The main crater is also water filled, although this water is way to cold. This lake, Öskjuvatn, is actually Icelands deepest lake. The area around the volcano is lunar like with typical lava landscape. And it is easy to understand why NASA chose this place for training before the missions to the moon. Askja had its latest eruption in 1961.
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