The main city in the eastern part of Iceland is Hofn in Hornafjordur. The view from Hofn is incredible with the biggest glacier in Iceland, Vatnajökull, close by. It is possible to take trips to the glacier. Please check this website.
On the way to Höfn you pass 'Jökulsárlón', glacial lagoon which is worth stopping by. You can sail between the icebergs on a boat in special trips, see here.
