Rail services have been disrupted as two stations in West Yorkshire are closed to allow for improvement works.
Network Rail said no trains would run in or out of Huddersfield and Dewsbury on Saturday and Sunday. But a replacement bus service was in place.
It is replacing the signal boxes at the stations with a digital Regional Operating Centre in York.
The company said it would result "in a more reliable, modern and cost-effective railway".
Network Rail say up to 25 replacement buses are running between Leeds, Manchester, Manchester Airport, Halifax, Wakefield, Huddersfield, Dewsbury, Stalybridge and Bradford.
TransPennine Express said it was not running any trains between Manchester and Leeds because of the work.
Its services from Newcastle, Middlesbrough, Scarborough, Hull, Manchester, Sheffield, Doncaster and Cleethorpes was also affected.
However, Northern Rail said it would be running trains between Manchester Victoria and Leeds via Halifax and Bradford during the works.
Rob McIntosh, managing director for the London North Eastern and East Midlands route, added: "The signalling system in this part of West Yorkshire is approaching the end of its operational life and we are taking this opportunity to replace it with the latest signal technology which will increase reliability, thereby reducing delays, while cutting the cost of running the railway for the taxpayer.
"There is never a good time to disrupt passengers but this work has been carefully planned over several years to maximise every minute available to us during this weekend."
Network Rail said this was the first of three weekend closures. It is also planning to shut the same stations during 28-29 October and 20-21 January, when the work is expected to be completed.