Complex sentence: The Downs Light Railway is the world's oldest private miniature railway, with a track gauge of 9½ inches, located in the grounds of the Downs Preparatory School (Colwall, Malvern, Worcestershire).
Split into simpler sentences: The Downs Light Railway is the world's oldest private miniature railway, with a track gauge of 9 1/2 inches. The Railway is located within the private grounds of the Downs Preparatory School (Colwall, Malvern, Worcestershire).