Network Rail hailed the success of its "orange army" of workers and revealed it had forked out £103m over the Christmas break upgrading Britain's rail network.
The work was carried out at almost 200 locations across the UK.
Meanwhile, commuters into London Waterloo will be pleased to hear that £4.5m of work scheduled at the station, or on the tracks leading up to it, was completed on time.
“Christmas provides us with a great chance to deliver vital aspects of our Railway Upgrade Plan while causing the least amount of disruption to passengers," said Becky Lumlock, route managing director at Network Rail.
Our orange army have worked around the clock through Christmas Day, Boxing Day, and New Year’s Day, providing a better railway for the growing number of passengers using the railway.
Network Rail said workers clocked up 15,000 hours in aggregate while Britons were enjoying themselves by tucking into their turkey dinner or letting their hair down at Christmas parties.
A key strand of the work at Waterloo included converting the former Eurostar international terminal back to domestic use.
“Our work will now continue behind the scenes in the international terminal, but I’d like to thank all those who gave up their Christmases in order to deliver these upgrades," said Lumlock.
A total of £800m has been committed to upgrading both Waterloo and the South West franchise rail infrastructure by Network Rail. The firm is aiming to boost capacity in and out of the iconic station by 30 per cent by the end of 2018.