On Riihimäki, southwest of Hatlamminmäki, is the valuable nature site Hatlamminsuo. The bog area is mainly a natural ombrotrophic raised bog. Hatlamminsuo has abundant and diverse fauna and vegetation. Several outdoor trails cross the area and during winter you can ski on the swamp. About one kilometre long nature rail runs mostly along duckboards and guideboards along it tell about the bog nature. There is an outdoor lodge near the bog.