The same river. The upper part is the Kjarra, the lower part the Thvera. It even has a third name in the middle, Ornolfsdalsa. It also has a significant tributary, the Litla-Thvera. It is one of the main tributaries to the glacial artery Hvita. The river Thvera/Kjarra is one of Iceland’s five star salmon fisheries.
It came in second in 1998 with almost 2.200 salmon and is always in the top five and rarely producing fewer than 1.800 fish in a season but year 2005 was one of the best year where Þvera og Kjarra landed 4151 salmon.
Along with the Nordura, it has Iceland's earliest runners, thus it opens the 5th of June. The early salmon are mostly 10 to 20 pounders. The grilse come later in vast schools. The river is in fact two seven rod beats, each with it's own luxury lodge. See fishing Statistic