There are two major tracks through Icelands interior: the Kjolur and the Sprengisandur. Last July I cycled both in surprisingly good weather. It was breathtakingly beautiful!
8 days through the largest uninhabited region in Europe, with amazing views of glaciers and stretches of lava desert.
In case you want to have a go, don't wait too long: they have this huge tarmac monster that they let out every spring!
Turn up the volume! The music is appropriately from two versions of À Sprengisandur, an old Icelandic song!