Someronlähde spring and ridges
There is an extensive sequence of longitudinal ridges going from Hausjärvi through Janakkala and all the way to Hämeenlinna. It was born after the ice age when currents of melting water from the ice separated different soils from eachother. The rougher grounds formed ridges the soil of which enables the absorption of rainwater and melting water into the groundwater. In fact, the ridges are the secret of the good quality of household water in Janakkala.
The finest open-surfaced spring in the ridge area is Someronlähde. A spring is born when the ground water inside the earth reaches the surface and erupts as surface water. The spring has biota of its own kind which flourishes all year round in cold water and shade.
The trails crisscrossing on top of the ridge and the ridge area are some of the most imposing places to exercise and hike even longer distances. From Turenki, you can hike along the ridge almost persistently to Kolmilammi in Hausjärvi. You can stop for a bit of lunch e.g. near Someronlähde spring at the hut of Janakkalan latu where hikers have a lean-to at their disposal.