Like most of the little islands around Iceland, Flatey is above all a stop for ornithologists and lovers of nature and tranquility.
My suggestion
Find out about doing the crossing between the Western Fjords and Snaefellsnes peninsula with a stop-over of a few hours on the island, even stay a little longer and spend the night if you can.
The East Fjords are a little known region, we often stop before, at the Jokulsarlon on route 1, where you can experience these places in a short amount of time. However, the view of the fjords can be amazing, and some places deserve that you take the time to discover them.
Grimsey is a small Icelandic island situated about 25 miles north of Iceland and the arctic polar circle runs through it. The spot is also ideal for watching bird colonies.
Only open when the centre of the country is no longer under snow, Route F35 is one of the most legendary in Iceland: rocky and wild, it winds its way through the most desolate and mountainous regions of the island. An exceptional road trip of discovery during the summer months!
The peninsula of Snæfellsnes, made famous by Jules Verne's novel Journey to the Centre of the Earth, contains most of Iceland's magnificent landscapes and is just a few hours' drive from the capital. In one day—or two, if you have the time—, you can discover superb panoramic views and various natural places of interest.