Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. The National Train Show or NTS, is held as part of the annual National Convention of the National Model Railroad Association. It is held in a different city each year (Cincinnati, Ohio in 2005 and Philadelphia, Pennsylvania in 2006, for example). It consists of industry exhibitors (railfan and model railroad targeted) and club layout exhibitions. In 2005, the NTS had about 300,000 square feet (28,000 m2) of display space and about 20,000 paying visitors.