First Scotrail diesel trains serve the high level. The high level railway approaches the station building through the Queen Street Tunnel, which runs beneath the Buchanan Galleries shopping centre to the Sighthill area northeast of the city centre whence the tracks converge from their various routes.
The low level, unlike the high level, is not a terminus, but rather an intermediate stop for the through line; it is, however, as heavily used as the high level. The line is also served by Charing Cross railway station and by High Street railway station, both of which lie within Glasgow city centre.
The stretch of this line between High Street, Queen Street and Charing Cross was in fact built before the Glasgow Subway, making it the oldest piece of underground railway in the city.
The station was originally built for the Edinburgh and Glasgow Railway, opened on 18 February 1842. The climb through the tunnel to Cowlairs was at 1 in 42 and until 1909 trains were hauled up on a rope operated by a stationary engine although experiments were carried out using banking engines between 1844/48. In 1945 there was a minor railway accident when a train leaving the station slipped to a standstill and rolled back into another train. Modern diesel trains have no difficulty with the climb.
The adjacent Buchanan Street station of the rival Caledonian Railway was closed on 7 November 1966 as a result of the Beeching axe and its services to Stirling, Perth, Inverness, Dundee and Aberdeen were transferred to Queen Street. This caused difficulties with longer trains, as Queen Street is in a confined position between George Square and the tunnel and barely takes six coaches. Current trains, however, are usually of two to four coaches, running more frequently.
Queen Street signal box, opened in 1881, was located on a gantry spanning the tracks close to the tunnel mouth. It closed on 26 February 1967 when control of the High Level station was transferred to a panel in Cowlairs signal box. That box was superseded by the new Cowlairs signalling centre on 28 December 1998.
The Low Level station had two signal boxes, 'Queen Street West' and 'Queen Street East'. Both boxes were situated over the tracks and both were closed on 8 February 1960. The low level lines came under the control of Yoker Signalling Centre (IECC) on 19 November 1989.
In early 2007, Network Rail began construction work on a new Glasgow Signalling Centre on the Cowlairs site which will ultimately replace signal boxes in the Glasgow area, north and south of the River Clyde.
Various schemes to link Queen Street to Central Station have been considered over the years, as Glasgow's weakest link in railway terms is that passengers travelling from the north of Scotland to the south via Glasgow and vice-versa have to traverse the city centre by road via a shuttle bus, or on foot. Even the Glasgow subway serves neither main line station, although Buchanan Street subway station is at least adjacent to Queen Street.
The preferred solution to the problem is a Crossrail initiative which would use a disused freight line which links High Street to the Gorbals area. This initiative was recently awarded a grant from the Scottish Government to investigate costs for possible link to be built between the two halves of the Glasgow rail network. A date of 2009 is estimated for completion of the project.
In August 2006, Network Rail revealed that it intends to redevelop Queen Street substantially, making use of the Hanover Street car park area to provide more retail space, and also to upgrade the station's entrances.
The CRT screens which displayed train timetables and passenger information were replaced with new LED information boards similar, but smaller in size, to those in Glasgow Central Station in January 2008.