Autumn (September – early November) is a fairly brief season in Iceland but also one of the most picturesque as the national parks turn brilliant shades of red, orange and yellow and vivid green moss covers ancient lava formations. Temperatures do become cooler and the sun starts setting once again though there's still plenty of daylight to enable the same range of activities you'd enjoy during the summer months.
What's different to the summer months is the lack of crowds and the lower prices for hotel rooms and flights. Plus, these months herald the beginning of the Northern Lights season and with warmer temperatures than winter, the lakes and rivers remain ice-free and reflect the spectacular display of colour on the water's surface. This makes it another great time of year to visit, especially for anyone with an interest in photography.