We loved the Askja / Viti area, and yes, it will take you most of the day on some very challanging roads (much of the trip feels like offroading, even though you are still on a "road"). It's about a 45 minute walk each way from the nearest parking lot to get to Lake Öskjuvatn and the Viti crater, part of it through snow (we were there in July; 12 day trip in total). We did not visit the West Fjord area at all this trip. We spent one night in the Myvatn area,
We did not return to Myvatn. but too the roads heading west and stayed the night at a farm on our way to the east coast .
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