Network Rail is confident that the £100 upgrade to track and signals in Nottinghamshire will provide huge benefits despite weeks of disruption ahead.
Justin Page, Route Master for the East Midlands, said when finished, the work will mean shorter journey times, more trains and a more reliable service in the county and throughout the region.
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Remaining dry overnight with lengthy clear periods.
Leah Washington, 17, had to have her left leg amputated after being trapped for hours on The Smiler rollercoaster at the theme park.
Fine and dry this evening and overnight with showers on Sunday afternoon.