An additional 186 Sunday train services have been announced by Transport for Wales.
The train operating company said Sunday services would be "transformed" from December by a 40% increase.
It said it was a "significant step towards the creation of a truly seven-day railway".
Economy and Transport Minister Ken Skates described it as a "dramatic increase" in services that would "increase connectivity".
Transport for Wales (TfW) said the new services would provide a boost to tourism and provide "essential links between cities, towns and villages".
The announcement includes:
- Four services in each direction between Llandudno Junction and Blaenau Ffestiniog, making it a year-round service
- The single service between Machynlleth and Pwllheli increased to five in each direction
- A Cardiff Central to Maesteg service for the first time
- More than doubling the number of services between Cardiff Central and Swansea from 14 to to 29
- Services from Cardiff to Gloucester starting two hours earlier than during the December 2018 timetable
- Faster direct journey times between Shrewsbury and Crewe with most Marches services stops removed, and stopping services increasing from nine to 16
- Services between Aberystwyth and Shrewsbury increasing from 16 to 21
- The Chester to Crewe summer service becoming year-round
- Thirty-two new services between Llandudno and Llandudno Junction
- Seven extra services between Rhymney and Cardiff
- Services to or from Caerphilly increasing from 16 to 45
- Hourly service between Treherbert and Cardiff, increasing from 15 to 28
- Enhanced Barry Island service, making it similar to the current summer timetable all year
- The Cardiff Queen Street to Cardiff Bay shuttle will increase from 100 services to 130 and will run until 22:00 - previously services finished at 19:00
- The summer timetable along the north Wales coast will run all year
Mr Skates said: "Transport is fundamental to the success of our economy in Wales and this dramatic increase in the number of Sunday services will increase connectivity between our cities, towns and villages.
"These services will improve access for social, recreational and educational opportunities, as well as employment opportunities. Later services will also increase options for people attending late night events across the country."
James Price, chief executive for Transport for Wales, said: "This significant increase in Sunday services is an important commitment that we made when we launched our new rail service over a year ago, and follows the successful launch of our May 2019 timetable, where we introduced direct services between Liverpool and Wrexham for the first time in decades.
"We hope that our customers and potential customers will welcome these services as an important step in building a transport network that the people of Wales can be truly proud of."