ScotRail's summer timetable will introduce full services between Glasgow and Edinburgh via the Airdrie and Bathgate link.
There will a half-hourly daytime direct service between Milngavie and Edinburgh six days a week, from 6.30am to 6.30pm on weekdays and 8.30am and 6.30pm on Saturdays.
There will also be six trains an hour between Glasgow and Coatbridge or Airdrie.
More trains will also call at Drumgelloch, with four trains an hour in each direction to and from Glasgow and Edinburgh.
The timetable, which starts on Sunday, May 22, also includes a 7.41pm Glasgow Queen Street to Aberdeen service, calling at Montrose, and a 6.12am Perth to Glasgow service, which will now start from Dundee at 5.58am – giving a first arrival from Dundee into Glasgow Queen Street one hour earlier than present.
There will also be a new 5.42pm service from Edinburgh Waverley to Glasgow Central, calling at Carstairs, Carluke, Wishaw and Motherwell, which will benefit Lanarkshire commuters.
There will also be a new Glasgow Central to Edinburgh train at 7.50pm, also calling at the Lanarkshire towns.
Steve Montgomery, ScotRail's managing director, said: "We are delighted to deliver the full Glasgow to Edinburgh via Airdrie and Bathgate timetable and to make other improvements to the timetable."
When the Airdrie to Bathgate line opened late last year, it was the longest stretch of rail track to be built in Scotland in more than a century.
The £300 million project saw 15 miles of new track laid and three new stations built at Armadale, Blackridge and Caldercruix.
Livingston North and Uphall stations were upgraded as part of the project.
The original line between Airdrie and Bathgate closed to passenger trains in 1956 and to freight services in 1982.
The new services have been hailed as good news for passengers.
Robert Samson, manager of the group Passenger Focus Scotland, said: "This is great news for passengers who will welcome the increased frequency and better links that these new services provide."