Complex sentence: It was closed when the railway was extended East with the opening of the Kilsyth and Bonnybridge Railway, a new station was built, Kilsyth New Station and this rendered the Old Station almost useless.
Split into simpler sentences: It was closed when the railway was extended east with the opening of the Kilsyth and Bonnybridge Railway. A new station was built, Kilsyth New Station and this rendered the Old Station almost useless.