Mountain roads in Iceland are opening, one by one, these days, following the melting of snow in spring. According to mbl.is, the Icelandic Road Administration has opened Road 208, from Sigalda to Landmannalaugar. A stretch of that same road east of Landmannalaugar remains closed, however, so you must drive back the same route you came. Dómadalsleið route is also closed.
The northernmost part of Road F26, to Aldeyjarfoss waterfall and to Hrafnabjargafossar waterfalls, beyond Bárðardalur valley, is now passable, but the closure by Ísólfsvatn lake is still in effect.
Road F333, Haukadalsvegur, has been opened, as has the easternmost part of Road F338, also called Skjaldbreiðarvegur. There, you can take Haukadalsvegur road onto Skjaldbreiðarvegur, from where you can drive east to Kjalvegur road.
For the latest information on passable mountain roads, visit road.is.