The Knoxville-Oak Ridge Innovation Valley, with its mild climate and abundant recreation, is gaining national notice as a quickly developing retirement area. Where to Retire magazine now ranks three areas within the Innovation Valley - Knoxville, Loudon and Gatlinburg -- among the top 100 most popular spots in the nation to retire. The Knoxville metro area, which had never appeared before on the list, jumped to 70th place on the top 100 list. For purposes of the magazine article, greater Knoxville was defined as Knox, Anderson and Union Counties. Norris Lake is mentioned as particularly hot spot for retirees. The authors ranked the Loudon area - which they defined as Loudon, Monroe and Roane Counties - the 96th most popular place in the country to retire. Greater Gatlinburg, which the authors defined broadly as Sevier and Jefferson Counties, ranked 97th on the list. Seveierville and Pigeon Forge are also mentioned as attractive retirement spots.The rankings appear in the lead article of the January/February edition of Where to Retire magazine, which has a circulation of more than 200,000. Findings are based upon a study by Wake Forest University demographer Charles F. Longino Jr. of the migration of Americans over 60 years of age. A total of 22 factors -- among them weather, cost of living and recreation - were considered in making the rankings. The State of Tennessee is making efforts to attract retirees to the region. The Tennessee Department of Economic and Community Development (ECD) has launched the Retire Tennessee program, which has a website, www.retiretennessee.org.The Where to Retire article also mentions the Crossville area, which jumped from from 92nd to 43rd place.