Nissan flows through soft soil layers that are easily undermined and make the landscape change. Therefore, the appearance of the river changes continuously. These are the changes of Nissan that created the landscape at Ettö.

Ettösjön and Svartviken are two bayes which now have stagnant water but previously entered into the flowing river.

Ettö has an open and lush suburban landscape with gardens, beaches and meadows. The majority of the reserve consists of open lumber with birches and juniper. However, the area West of Svartvik is made up of barrels forest. Along Nissan there are al and hägg, furthest north of the spruce and pines.

The area is flooded almost every spring, as Nissan rinses nutritious water across the nutritional low soil. The whole area is grazed, which means that an interesting and rich flora thrives here. The meadows are also kept open by mowing and clearing.

Ettö Nature Reserve was established in 1970. The area is approximately 15 ha. It is located along Highway 26 (Nissastigen) near Hestra. Parking space is located just north of the reserve.