KNOXVILLE, Tenn. — Knoxville’s urban wilderness is expanding, and the latest addition to fun-filled outdoor space is the William Hastie Natural Area in South Knoxville. On Thursday, city of Knoxville officials, Appalachian Mountain Bike Club volunteers and donors close to the project cut the ribbon on four new trails. The added 2 miles of urban outdoor space is a welcome addition for those who love to hike, walk, run, rock climb and mountain bike. The 27-acre project has been just over a year in the making.