The main core of the route runs from Edinburgh Waverley to Helensburgh Central via Bathgate and Glasgow Queen Street (Low Level).

Notable withdrawals of passenger service occurred on: In 1960 the remainder of the North Clyde suburban system (Airdrie, Springburn and Bridgeton Central to Milngavie, Balloch Pier and Helensburgh Central, including both routes between Partick and Dalmuir) underwent electrification.

On 17 December 1979, Partickhill station was replaced by the new Partick (Interchange) slightly to the south, which provides a connection with the Subway.

Pleasure steamer operations on Loch Lomond ceased in the 1980s, leading to the closure of Balloch Pier on 28 September 1986.

The catenary from the closed section to Balloch Pier was then used to reopen the line east of Airdrie to a new terminus at Drumgelloch in May 1989.

In 2005, the Scottish Executive declared that in line with plans to upgrade the remaining section of the A8 road to motorway standard, public transport links between Glasgow and Edinburgh must also be improved.

Work commenced with a sod cutting ceremony at Livingston North in June 2007, with reinstatement of double track between Newbridge and Bathgate being the first stage, completed in October 2008.

[3] As part of the wider Edinburgh to Glasgow Improvement Programme (EGIP), plans were made to electrify the Cumbernauld Line and the Garngad Chord, adjacent to Springburn, creating an electrified link between the Springburn branch of the North Clyde Line and the Cumbernauld Line - then operated by diesel multiple units into Glasgow Queen Street High Level - allowing electric service from Cumbernauld into the Low Level of Glasgow Queen Street, and thus connecting Cumbernauld to destinations west of Glasgow, whilst also freeing up capacity on the High Level lines out of Queen Street.

Electrification brought the introduction of the legendary and locally-built Class 303 EMUs, operated from a new depot at the former Hyndland terminus station.

In the 1970s, a new electric locomotive/EMU depot was built at Shields Road south of the Clyde, and this took over maintenance of the EMUs used on the Cathcart Circle and Inverclyde Lines, including all of the Class 311s.

In 1987, Hyndland depot closed and was replaced by new carriage sidings at Yoker, with maintenance transferred to Shields Road.

However, it was not until 1990 that a start was made on replacing the Class 303s, which still operated the great majority of services on the North Clyde Line.

With many passengers travelling north–south through the city centre having to walk or use a shuttle bus between Central and Queen Street stations, SPT has long proposed a direct rail link between the North Clyde system and the lines radiating from Glasgow Central (High Level).

The plan would involve re-opening to passenger traffic the freight-only City Union Line between Shields Junction and Bellgrove, and building a new curve between Gallowgate and High Street.

Reopening of the closed line from Strathbungo to Gorbals would allow trains from Barrhead and East Kilbride to use Crossrail.