People need to be able to trust the north's trains again, Andy Burnham and Steve Rotheram write.
Services from stations including Manchester Piccadilly, Liverpool Lime Street and Lancaster are affected.
There are only 80,000 discounted tickets available, so book now if you can.
Northern's May timetable changes saw up to 310 trains a day cancelled.
Around 80 services will not run.
It's estimated businesses have lost almost £38 million because of Northern Rail disruption.
'Late to work and even later home'.
The chaos cost £38 million according to a new report.