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Tuesday 29 Sep 2026

New details announced for multi-million-pound investment to boost reliability of North Wales Coast railway

Region & Route:

Wales & Western: Wales & Borders

This once-in-a-generation programme will deliver years’ worth of improvements during a four-week railway closure in January 2027.

More than £25m will be invested in the North Wales Coast railway in January 2027, as Network Rail delivers a major programme of improvements to boost reliability, capacity and safety on this vital passenger and freight route.

The once-in-a-generation programme will see engineers working at locations across the railway between Chester and Holyhead, renewing track and other infrastructure - some of which has been in place for more than 50 years.

To allow this huge package of work to be delivered safely and efficiently, the North Wales Coast line will close for four weeks from Saturday 9 January until Saturday 6 February 2027.

For the first three weeks, the railway will be closed between Chester and Holyhead, including the Conwy Valley line and Llandudno Junction to Llandudno. During the fourth week, the closure will reduce to between Llandudno Junction and Holyhead.

Network Rail has worked with its engineering teams to reduce the closure between Chester and Llandudno Junction from four weeks to three, and is continuing to work with its industry partners to reduce the impact of disruption for passengers and communities.

Rail replacement services will operate during the closure, with detailed travel arrangements expected to be confirmed in autumn 2026.

The £25m investment includes:

• Renewing track through the Grade I-listed Conwy Tubular Railway Bridge, where the existing track dates back to 1978.
• Major track and drainage improvements in Bodorgan Tunnel, replacing infrastructure dating back to 1972 and helping reduce the risk of flooding.
• Track renewal and ground improvements at Penmaenbach, where sections of track were last renewed in 1986.
• Track and points improvements at Holyhead and Llandudno.
• Platform improvements at Llandudno Junction.
• Work at four level crossings, east of Bangor.
• Around £1.4m of vegetation management across nine locations, alongside extensive maintenance throughout the route.
• Two new fully accessible footbridges at Prestatyn and Abergele, supporting the closure of four high-risk level crossings.

The work will be delivered by rail using 22 engineering trains and specialist on-track machinery, bringing in more than 3,000 concrete sleepers and 9,000 tonnes of ballast, while around 9,800 tonnes of spoil will be removed for recycling and reuse on future railway projects.

The investment builds on the introduction of the new North Wales timetable in May 2026, which delivered a 50% increase in Transport for Wales services - the biggest timetable improvement in North Wales for a generation.

With more trains now using the railway, the January closure will also allow Network Rail teams to carry out additional maintenance alongside the major renewals. Completing this large amount of complex work in one four-week programme will reduce the need for repeated weekend closures over the months and years ahead, minimising disruption for passengers, residents and local businesses.

Emma Osborn, Passenger Strategy Director at Network Rail Wales and Borders route, said: “This is a once-in-a-generation investment in the North Wales Coast railway and a huge opportunity to renew and improve infrastructure right across this vital route.

“Investment on this scale inevitably means some temporary disruption while we carry out the work, and we recognise closing the railway will have an impact on customers and communities.

“But by bringing years’ worth of complex work together into one intensive programme, we can deliver it more safely and efficiently, while avoiding a prolonged series of disruptive weekend closures.

“The long-term benefits for passengers and freight customers will far outweigh this temporary disruption, with a safer, more reliable railway that is better equipped to support the increased number of services now running across North Wales.

“We’re working closely with Transport for Wales and Avanti West Coast to keep passengers moving and we thank everyone in advance for their patience while we deliver this major investment.”

Colin Lea, Planning & Performance Director for Transport for Wales said: "As we see passenger numbers and service frequencies across North Wales grow, working alongside our partners at Network Rail is essential to ensure our infrastructure can support that demand.

"Essential track maintenance, tunnel drainage, and new accessible footbridges will help deliver a more reliable service and better stations for the communities we serve.

"We know railway closures are disruptive to our passengers, and we appreciate their patience. We remain committed to keeping North Wales moving throughout January, and full details on alternative travel arrangements will be shared this Autumn.”

Chris Liptrot, Operations Director at Avanti West Coast, said: “While Network Rail carries out these improvements, there will be changes to services on our North Wales route.

“We are working closely with Network Rail and our industry partners to ensure customers are kept informed about how their journeys may be affected. Once the timetable has been confirmed, customers planning to travel during this period are advised to check the Avanti West Coast and National Rail Enquiries websites for the latest travel information.”

END

Manylion newydd yn cael ei gyhoeddi am fuddsoddiad gwerth miliynau o bunnoedd ar gyfer gwella dibynadwyedd ar reilffordd Arfordir Gogledd Cymru

Bydd y rhaglen hon, sy’n gyfle euraid, yn cyflawni gwerth blynyddoedd o welliannau pan fydd y rheilffordd ar gau am bedair wythnos yn ystod mis Ionawr 2027.

Caiff mwy na £25 miliwn ei fuddsoddi yn rheilffordd Arfordir Gogledd Cymru ym mis Ionawr 2027, wrth i Network Rail gyflawni rhaglen fawr o welliannau er mwyn hybu dibynadwyedd a chapasiti ar y llwybr hwn sy’n hanfodol i deithwyr a threnau nwyddau.

Fel rhan o’r rhaglen hon, sy’n gyfle euraid, bydd peirianwyr yn gweithio mewn lleoliadau ar draws y rheilffordd rhwng Caer a Chaergybi, yn adnewyddu’r trac a darnau eraill o seilwaith – y mae rhai ohonynt wedi bod yn weithredol ers mwy na hanner canrif.

Er mwyn caniatáu i’r pecyn mawr hwn o waith gael ei wneud yn ddiogel ac yn effeithlon, bydd llwybr Arfordir Gogledd Cymru ar gau am bedair wythnos o ddydd Sadwrn 9 Ionawr i ddydd Sadwrn 6 Chwefror 2027.

Yn ystod y tair wythnos gyntaf, bydd y rheilffordd ar gau rhwng Caer a Chaergybi, gan gynnwys llinell Dyffryn Conwy a Chyffordd Llandudno i Landudno. Yn ystod y bedwaredd wythnos, bydd llai o’r rheilffordd ar gau, sef y darn rhwng Cyffordd Llandudno a Chaergybi.

Mae Network Rail wedi gweithio gyda’i dimau peirianyddol i leihau’r cyfnod y bydd y rheilffordd ar gau rhwng Caer a Chyffordd Llandudno, i lawr o bedair wythnos i dair.

Bydd bysiau’n rhedeg yn lle trenau pan fydd y rheilffordd ar gau. Disgwylir cadarnhau’r trefniadau teithio manwl yn hydref 2026.

Mae’r buddsoddiad gwerth £25 miliwn yn cynnwys:

• Adnewyddu’r trac ar Bont Reilffordd Diwbaidd Conwy, sy’n strwythur rhestredig Gradd I. Mae’r trac presennol yn dyddio’n ôl i 1978.
• Gwelliannau mawr i’r trac a’r draeniau yn Nhwnnel Bodorgan, yn adnewyddu seilwaith sy’n dyddio’n ôl i 1972 ac yn helpu lleihau risg llifogydd.
• Adnewyddu’r trac a gwelliannau i’r tir ym Mhenmaen-bach, lle na chafodd darnau o’r trac eu hadnewyddu ers 1986.
• Gwelliannau i’r trac a’r pwyntiau yng Nghaergybi a Llandudno.
• Gwelliannau i’r platfform yng Nghyffordd Llandudno.
• Gwaith ar bedair croesfan wastad, i’r dwyrain o Fangor.
• Gwaith rheoli llystyfiant gwerth oddeutu £1.4 miliwn mewn naw lleoliad, ynghyd â gwaith cynnal a chadw helaeth ar hyd y llwybr.
• Dwy bont droed gwbl hygyrch newydd ym Mhrestatyn ac Abergele, yn caniatáu inni gau pedair croesfan wastad risg uchel.

Mae’r buddsoddiad yn adeiladu ar y gwaith i gyflwyno amserlen newydd Gogledd Cymru ym mis Mai 2026, pan gynyddwyd nifer gwasanaethau Trafnidiaeth Cymru 50% - y gwelliant mwyaf i amserlen Gogledd Cymru ers degawdau.

Gyda mwy o drenau’n defnyddio’r rheilffordd, bydd cau’r rheilffordd ym mis Ionawr hefyd yn caniatáu i dimau Network Rail wneud gwaith cynnal a chadw ychwanegol, yn ogystal â’r prif waith adnewyddu.

Trwy gwblhau’r holl waith cymhleth hwn yn ystod un rhaglen pedair wythnos, bydd llai o angen cau’r rheilffordd ar benwythnosau dros y misoedd a’r blynyddoedd nesaf, gan leihau’r tarfu ar deithwyr, trigolion a busnesau lleol cymaint â phosibl.

Dywedodd Emma Osborn, Cyfarwyddwr Strategaeth i Deithwyr llwybr Cymru a’r Gororau Network Rail:“Mae’r buddsoddiad unigryw hwn yn rheilffordd Arfordir Gogledd Cymru yn gyfle euraid i adnewyddu a gwella seilwaith ar draws y llwybr pwysig hwn.

“Mae’n anochel y bydd buddsoddiad ar raddfa mor fawr yn achosi rhywfaint o darfu dros dro wrth inni gwblhau’r gwaith, a gwyddom y bydd cau’r rheilffordd yn effeithio ar gwsmeriaid a chymunedau.

“Ond trwy ddod â gwerth blynyddoedd o waith cymhleth at ei gilydd mewn un rhaglen ddwys, gallwn ei gyflawni’n fwy diogel ac effeithlon, ac osgoi cyfres estynedig o benwythnosau pan fydd y rheilffordd ar gau, sy’n tarfu ar ein cwsmeriaid.

“Bydd y buddion hirdymor i deithwyr a threnau nwyddau yn drech na’r cyfnod o darfu dros dro, trwy gynnig rheilffordd fwy diogel a dibynadwy sydd â’r gallu i gefnogi’r nifer ychwanegol o wasanaethau sydd bellach yn rhedeg ar draws Gogledd Cymru.

“Rydym yn gweithio’n agos â Thrafnidiaeth Cymru ac Avanti West Coast i gadw’r teithwyr i symud. Diolch i bawb ymlaen llaw am eu hamynedd wrth inni gyflenwi’r buddsoddiad mawr hwn.”

Dywedodd Colin Lea, Cyfarwyddwr Cynllunio a Pherfformiad Trafnidiaeth Cymru: "Wrth i ni weld cynnydd yn nifer y teithwyr ac amlder y gwasanaethau ar draws gogledd Cymru, mae gweithio ochr yn ochr â'n partneriaid yn Network Rail yn hanfodol i sicrhau y gall ein seilwaith gefnogi'r galw hwnnw.

"Bydd gwaith cynnal a chadw traciau hanfodol, draenio twneli, a phontydd troed hygyrch newydd yn helpu i ddarparu gwasanaeth mwy dibynadwy a gorsafoedd gwell i'r cymunedau rydyn ni'n eu gwasanaethu.

 “Rydyn ni'n gwybod bod cau rheilffyrdd yn amharu ar ein teithwyr, ac rydyn ni'n gwerthfawrogi eu hamynedd. Rydyn ni'n parhau i fod wedi ymrwymo i gadw gogledd Cymru i symud drwy gydol mis Ionawr, a bydd manylion llawn am drefniadau teithio yn cael eu rhannu'r Hydref hwn."

Dywedodd Chris Liptrot, Cyfarwyddwr Gweithrediadau Avanti West Coast: “Bydd newidiadau i’n gwasanaethau ar lwybr Gogledd Cymru wrth i Network Rail gyflawni’r gwelliannau hyn.

“Rydym yn gweithio’n agos â Network Rail a’n partneriaid yn y diwydiant i sicrhau y caiff cwsmeriaid y wybodaeth ddiweddaraf am sut yr effeithir ar eu teithiau. Pan fydd yr amserlen wedi’i chadarnhau, argymhellwn i deithwyr sy’n bwriadu teithio yn ystod y cyfnod hwn i wirio gwefannau Avanti West Coast a’r Ymholiadau Rheilffyrdd Cenedlaethol i gael y wybodaeth ddiweddaraf am deithio.”