The Belgrave line is a commuter railway line in the city of Melbourne, Victoria, Australia. Operated by Metro Trains Melbourne, it is the city's fourth longest metropolitan railway line at . The line runs from Flinders Street station in central Melbourne to Belgrave station in the east, serving 31 stations via Burnley, Box Hill, Ringwood, and Upper Ferntree Gully. Beyond Belgrave, the narrow-gauge line has been restored as the Puffing Billy Railway, which runs tourist services to the original terminus of Gembrook. The line operates for approximately 19 hours a day (from approximately 5:00 am to around 12:00 am) with 24 hour service available on Friday and Saturday nights. During peak hour, headways of up to 15 minutes are operated with services every 20-30 minutes during off-peak hours. Trains on the Belgrave line run with a two three-car formations of X'Trapolis 100 trainsets. Sections of the Belgrave line opened as early as 1889, with the line fully extended and re-gauged to Belgrave by 1962. The line was built to connect Melbourne and Ringwood with the rural towns of Bayswater, Boronia, Upper Ferntree Gully, and Belgrave, amongst others. Since the 2010s, due to the heavily utilised infrastructure of the Belgrave line, significant improvements and upgrades have been made. Different packages of works have upgraded the corridor to replace sleepers, upgrading signalling technology, the introduction of new rolling stock, and the removal 7 out of the 9 remaining level crossings. History 19th century A rail branch was constructed from Ringwood to Upper Ferntree Gully in December 1889. A narrow-gauge line was opened from Upper Ferntree Gully to Gembrook station in December 1900, the second of four experimental narrow-gauge lines built by the Victorian Railways. These two lines would become joined and standardised to form the Belgrave railway line in the 20th century. 20th century In 1921, the narrow-gauge section from Upper Ferntree Gully to Belgrave was converted to automatic signalling, the first such instance on single track in the Southern Hemisphere. This section was then reverted to Staff and Ticket safeworking in 1930. Electrification of the railway to Upper Ferntree Gully was implemented in November 1925. Following a landslide in 1953, the narrow-gauge line was formally closed in April 1954, although services resumed as far as Belgrave for some "farewell specials", and then for the Puffing Billy Preservation Society until services ceased again in February 1958. The line was partly duplicated between