The Glasgow to Edinburgh shuttle service will increase to eight trains an hour during August to improve connections for festivalgoers.

ScotRail announced trains between Queen Street and Waverley will run more frequently, have more seats and operate later throughout the month.

There will be an extra service to Dundee, additional night-time trains to North Berwick and Garscadden in Glasgow on Fridays and Saturdays, and later services to Glenrothes via Dunfermline on Fridays.

The changes will be phased in from Friday ahead of a full expanded service from Monday to coincide with the reopening of the Queen Street tunnel after a £60m upgrade.

Services to Edinburgh from Queen Street high level via Falkirk High plus low level services via Airdrie and Bathgate will also be restarted after the tunnel is opened.

Edinburgh's festival season will get into full swing with the launch of three of the biggest events on Friday - the Edinburgh International Festival (EIF), Edinburgh Festival Fringe and the Royal Edinburgh Military Tattoo.

Edinburgh International Book Festival also takes place this month.

ScotRail said peak services will have extra carriages and the last train from Edinburgh will leave at the later time of 12.30am.

Cathy Craig, ScotRail's commercial director, said: "We want to help as many people as possible get to and from the capital so that they can be part of the incredible festival experience.

"Trains are always busy during the festivals. If people can plan ahead, give themselves plenty of time and consider using all of the services that are going to Edinburgh - not just those that operate on the high level - then I am confident that we will be able to carry more people than ever before."