My mother was Icelandic and we visited about 20 years ago and saw all the relatives. A good thread from Archerp. Gullfoss the waterfalls are beautiful. Enjoy the smell of the sulphur water, geothermally heated showers.There is also the Hand Knitting Icelandic Association with an outlet in Rekjavik. May be try some skyr (a kind of yoghurt and hardfiskur, a rather tasty dried fish. We thoroughly enjoyed our visit and the scenery is unique. Our daughter went horse riding up there when she visited, during her gap year, but it might not be quite the weather for it for you!