HO scale is the most common in Model Railroading, with a ratio of 1/87.1, or 3.5 mm per foot.
The CentraMod HO group has two permanent layouts in the Moody Depot clubhouse. The first is the Historic Temple layout, modeling Temple, Texas circa 1932. Members have scratch built the Temple Santa Fe depot, Harvey House and several other signature Temple buildings. The second is the Operations layout, the Ft.Worth Temple and Gulf railroad, a proto-freelanced railroad running through the plains of Texas from Ft.Worth to Houston.