The overall diameter of the iron armillary is 17" encompassing the entire length of the arrow; the circle portion of the armillary is 13"DIA. The armillary is iron, and exposure to the elements will cause it to rust over time. If a rusted look is not for you, regular application of polyurethane or other protective coating (available at your local hardware store) will help the armillary maintain its pristine appearance for years to come. Covering the armillary in winter is also recommended. Pedestal no longer available.