The Carrickmines/Bride's Glen section was also intended to have terminated into what should have a "Celtic Tiger" town centre, similar to the Tallaght area stops, until the Line B2 extension to Fassaroe/Bray was built. This is why, as of 2018, this end of the Green Line seemingly goes to the middle of nowhere, through fields, as nearly all the property that was intended to be serviced by the line, was never built. This is also why there were unused "Ghost" stops built, to serve these unbuilt areas. There are some other cosmetic differences between the Harcourt Street Line and the current Green Line, such as the positioning of the Ranelagh stop. The location of Ranelagh on the former line was at the current Beechwood stop. The old Ranelagh stop was the last stop on the old line before the train reached the city. Luas Cross City (), formerly called Luas BXD, is an extension to the Green Line which runs from St. Stephen's Green to Broombridge railway station. Construction of Luas Cross City began in June 2013 and it opened on 9 December 2017. The Rosie Hackett Bridge carrying the new line over the river Liffey was opened on 20 May 2014. The new section begins at the former city centre terminus, St. Stephen's Green, crosses the Red Line near the Abbey stop, and continues northwards, terminating at Broombridge station. There it connects passengers using Iarnród Éireann commuter services to Maynooth railway station and M3 Parkway railway station. The line re-uses some existing bridges and viaducts and has had new bridges specially constructed. The new build William Dargan Bridge at Dundrum crosses the Slang River. The River Liffey is crossed by the new Rosie Hackett Bridge southbound and the existing O'Connell Bridge northbound. The River Dodder is crossed by the Nine Arches Bridge originally constructed for the Harcourt Street railway line in 1854. The Green line initially was provisioned with a works depot just past the Sandyford terminus and opposite the old Stillorgan Railway station building. The depot could stable 32 trams. When the Green line was extended to Broombridge a further depot was constructed over part of the old Liffey Junction site. It was named "Hamilton Depot" in honour of William Rowan Hamilton who developed the quaternion mathematical number system. The primary control facility for the Luas system for such functions as power and signally lies at the Red line Luas depot at Red Cow.