Celebrate the arrival of spring next Friday, March 20, with guided hikes in Rock Island State Park on Saturday – one to the Blue Hole Trail at 10 a.m. and one to Bone Cave at 2 p.m.The hike to Bone Cave will go all the way to the entrance of the cave, stop and discuss the natural and historical aspects of the area. It is approximately half a mile long and does include a fairly steep hill. Snack and water are recommended.