Bridge of Weir is a village within the Renfrewshire council area and wider historic county of Renfrewshire in the west central Lowlands of Scotland. Lying within the Gryffe Valley, Bridge of Weir owes its name to the historic crossing point that it provided over the River Gryffe. The village was initially formed around industries such as cotton and leather, reliant on the power of the river. These industries brought about its expansion in the 18th century in land attached to the 15th century Ranfurly Castle situated between the two established parishes of Kilbarchan and Houston and Killellan. A rail connection, as part of the Glasgow and South Western Railway, in the 1860s, significantly supported the village's development.