With some £21m in funding from the Department of Transport, after audits found many were in poor repair, charity Sustrans has been working nationwide to make many more accessible for all.
Now, with work underway with local authorities in Yorkshire to improve inclusivity, a changing face is emerging across some of the region's best loved routes.
For Lee Thompson, Yorkshire's partnership manager for Sustrans, this is crucial in embedding a culture of active travel, amid concerns over climate change and sustainable futures.
"We live in a world that has many such challenges," he said. "This is an absolutely essential part of the solution.
"In its simplest form, it's about aiming to make the world a better place and to encourage people to travel in a way that's good for the environment.
"It does feel like we are heading in the right direction."
Sustrans' audits in 2018 found around half of the NCN was in poor repair, and revealed a vision to remove barriers and improve the surfaces and safety of routes.
Over recent months work is progressing at pace across parts of Yorkshire, and to bring the network to a standard which is safe for a 'sensible 12 year old'.
At Bentley Park, in Doncaster, a section of the Trans Pennine Trail has been improved to allow access for people with disabilities, with similar improvements to a route in Barnsley.
In York, sections of the Solar System Way are being upgraded, with plans in place to extend West Yorkshire s Castleford Greenway, and a new section of route for the Wetherby Railway Path.
And along Yorkshire's coast, work is underway to improve the scenic Cinder Track, which runs between Scarborough and Whitby.
Yorkshire is "blessed" with its industrial heritage alongside scenic, rural landscapes, Mr Thompson has said. With a network of disused railways and canals put in place to fuel the region's industrial revolution, many of these were taken on by Sustrans in the 1970s as legacy projects for today's NCN.
"What we've got is this network, of urban and rural and historical landscapes, which really give a flavour of Yorkshire's heritage - and contrasts with some of the rurality we have," he said. "We have made the most of it, and we would love to see it better connected.
"It comes down to hearts and minds and planning and policy," he added. "It has to be backed financially. If we can get hearts and minds on board, that recognise the impact and benefits of active travel, and match that with budgets, then we can seriously start to affect transformative change."
Mr Thompson cites the city of York as a good example of where change has been embraced, and is keen to build on Northern successes seen in areas such as Manchester. With events such as the Grand Depart and Tour de Yorkshire, he added, cycling is increasingly popular.
Broader gains of active travel are now recognised, for personal health and wellbeing and for the environment, he believes.
"It's fair to say 10,15 years ago, active travel was rarely mentioned and was probably a footnote on agendas," said Mr Thompson. "We live in a time where that feels like it's changing."
While funding for changes to accessibility and inclusivity comes from groups such as the DfT and Highways England, and is delivered through Sustrans, it is often local authorities that put improvements into practice, with the support of local landowners.
Among partners involved in the region's projects is Sheffield City Region, the West Yorkshire Combined Authority City Connect scheme, and City of York Council, as well as the Trans Pennine Trail, Scarborough and Whitby Councils, Doncaster and Barnsley Councils alongside local partners.