the new Firbeck and Harworth collieries coming into full production and their branch lines becoming part of the SYJR. This produced a net revenue for the SYJR of £81,000 – equal to about £5.3 million in 2020 prices, an astonishing figure for a line (excluding sidings) of just under . By the end of 1929, capital expenditure on the SYJR had reached more than £710,000. As of 2010, only Maltby colliery was still producing coal, around 1.2 million tonnes a year according to the owners, but this last one closed in March 2013. The route used encounters hilly country, and there are three viaducts, the largest being at the village of Slade Hooton one over the East Coast Main Line at Potteric Carr and the last being on the now lifted Harworth Branch passing over the A631 to the west of the village of Tickhill and, a rising gradient for most of its journey. The highest point of the line is in the vicinity of Brookhouse viaduct. Maltby signal box which controlled train entry into and out of the colliery at Maltby is still operating and is the last mechanical Great Central type 5 designed signal box left on the line (built 1912), This box is actually within the town of Doncaster's boundary – so technically the box is the last mechanical signal box still in operation within the town of Doncaster.(See British Ordnance Survey map for Doncaster area village of Stainton) Passenger services There were three stations on the railway, these being , and , all of them being situated away from the villages in their title. Four passenger trains each way daily were operated by the GCR and the GNR and these ran between , over the Great Northern Main Line as far as Potteric Carr junction, and Shireoaks. Services called at all stations on the SYJR and , on the Great Central and Midland Joint line. The joint passenger service operated for just one year before the GNR services were discontinued, reducing the service to two GCR trains with an extra one on Saturday. From April 1920, the service was extended to . Passenger traffic over the line was never great, with the largest total number of travellers – 60,220 – being recorded in 1913. The service became Saturdays-only in June 1917 until April 1920 but was suspended from April 1926 to July 1927 due to the