Mackenzie River is a must do, Lynda. It's about 29 miles from top to bottom. Most people park at the bottom at the ranger station and shuttle to the top. The first 14 miles of twisty trail through lava and forest you need your a-game for, and the bottom half is smooth cedar forest trail.
Bend is supposed to be great but I don't know the trails there. Have fun, fall is a great time of year.