Thousands of commuters have been affected by a 48-hour strike staged by railway signal workers in Scotland.
A notice board at Glasgow Central Station conveys the message
Several services were suspended from mid-morning on Wednesday and will not resume until peak times on Friday due to the dispute over working hours.
Services on some routes, including Glasgow to Edinburgh, were reduced, but Network Rail claimed its priority was to run as many trains as possible.
First Minister Jack MacConnell voiced concerns about the strike.
His spokeman said: "The first minister expressed his disappointment at the effect this is going to have in terms of disruption to travellers and commuters and is hoping that those responsible will be able to get it sorted as quickly as possible."
About 400 signalling and supervisory staff walked out at 1200 GMT in a row over working conditions, forcing the cancellation of hundreds of services.
The first rail strike in Scotland for nearly four years, it followed the collapse of talks between Network Rail (NR) and the National Union of Rail, Maritime and Transport Workers (RMT).
The dispute centres on a failure to honour a 35-hour week agreement and the abuse of rostering agreements, according to the union.
RMT general secretary Bob Crow said: "Reports from RMT organisers and reps across Scotland tell us that our members' strike is absolutely rock-solid.
"Network Rail should understand that our members are determined to achieve the 35-hour week we agreed to last July, and it is the company that holds a very simple solution in its hands.
"Network Rail now has the choice of engaging constructively with us to resolve this dispute or facing a ballot of our signalling members throughout Britain."
However, David Simpson, route director for Network Rail Scotland, labelled the action "regrettable" and "unnecessary" and insisted the company was willing to engage in discussions with RMT.
"We've offered to go to (arbitration service) ACAS to have this matter resolved, but RMT have refused that and passengers are suffering as a result," he said.
The director insisted safety was not being put at risk during the skeleton rail services but the RMT claimed the limited trains that ran on Wednesday did so "with the help of inadequately trained managers" from England.
First ScotRail said it was "as prepared as can be" for the strike, but warned passengers that reduced frequency and capacity on certain routes would continue.
The service between Edinburgh Waverley and Glasgow Queen Street is due to run every 30 minutes for the duration of the dispute.
How the rail strike has hit some travellers
The last train is scheduled to leave Glasgow at 1800 GMT, while the last departure from Edinburgh will be at 1745 GMT.
Reduced services are also operating between Edinburgh and Fife, Bathgate, North Berwick and Stirling.
A number of services from Glasgow will run on reduced timetables, while others have been cancelled until Friday afternoon.
Services suspended include the routes to Whifflet, Paisley Canal, Dumfries and Carlisle, Wemyss Bay and the Cathcart circle.
No trains are running on the services between Aberdeen and Glasgow, Edinburgh and Inverness.
Services from Inverness to Glasgow, Edinburgh, Wick, Thurso and Kyle of Lochalsh have also been cancelled.
The Caledonian Sleeper service between Scotland and London is not running on Wednesday or Thursday, but should operate on Friday.
The other cancelled services include those between Perth and Glasgow and those from Edinburgh to West Calder, Newcraighall and Glasgow via Shotts.
The rail company apologised to passengers and urged people to check its website for the latest details of its services.
James King, who is on the board of the rail watchdog Passenger Focus, said travellers felt bewildered by the action.
He said: "Passengers are not really interested in the detail of it, they're just interested in their day-to-day journey to work, to the doctors, dentist, hospital, whatever it is."
Stagecoach said it filled most of the 1,200 extra coach seats it provided on its Scottish Citylink and megabus for those affected by the strike.
More than 20 additional coaches were put on standby in Aberdeen, Dundee, Edinburgh, Glasgow, Inverness and Perth.
HOW PASSENGERS HAVE BEEN AFFECTED ACROSS SCOTLAND