Iso-Ruonanen is a lake by the hiking trail Peuran polku. It is the next lake you will reach if you start your hike from lake Valkeinen. Iso-Ruonanen is a long but narrow lake, which gives you the opportunity to hike along side it. When you reach approximately the middle point of the lake, you can stop for a break as there is a table set by the trail. The table set was renewed in 2021.