Iceland is a glacier paradise. Here you can find the largest ice cap in Europe along with some amazingly picturesque outlet glaciers. Many of these glacier tongues are very easy to access, allowing Iceland to offer a great selection of glacier walking tours to its visitors.
When you walk up to a mountain like Sveinstindur you are in for a treat. At the top, you have a spectacular view of a significant portion of the Icelandic highland. On your way up you start to see more and more of mountains, lava, glaciers, lakes, and rivers.
There are three conditions you need in order to see the Northern Lights: darkness, clear sky, and at least some aurora activity. With relatively good weather (read, more chance for clear skies) and about 10 hours of darkness, September is a very good month to see auroras in Iceland.
The length of the day is an important consideration that you need to be aware of. We experience very bright nights in Iceland from June to August, but the nights are extremely long and dark in winter. The length of daylight can also differ significantly in the northern and southern parts of the country.
The difficulty level of a trail can vary according to the weather and the season, the weight of your backpack is also an important factor to consider. Check the walking distance, estimated hiking time, and also the elevations.
This might sound ridiculous, but it is a lifesaver. No matter what season it is.