South Western Railway Christmas line closures planned in Hampshire
South Western Railway passengers are being warned to plan their journeys over the Christmas period due to £8m engineering works in Hampshire.
The line between Southampton Airport Parkway and Southampton Central, and between Fareham and Southampton Central will shut from 24 December to 1 January.
London, Bournemouth, Poole and Weymouth journeys will also be affected.
Network Rail said the work would make journeys "more reliable".
Buses will replace trains in the area of the line closures, but passengers have been advised to travel before Christmas Eve.
Services on 10 and 17 December will also be affected by the work.
More than 200 sets of engineering works are planned by Network Rail during the festive period.
The firm said it was the least disruptive time to carry out the work, and said 95% of the network would be unaffected.
The work in Hampshire, which it described as "vital", is part of an £8m investment that will see about 6,000m (19,700ft) of cabling and 200m (660ft) of track replaced.
Network Rail said the work would also help reduce track noise for neighbouring residents.
More than 100 engineers and staff will be working shifts, 24 hours a day, to carry out the work, it said.