THEY take in some of Scotland’s most breath-taking landscapes – from the bonnie banks of Loch Lomond to the craggy heights of the Cairngorms.

Now campaigners have renewed calls for more national parks to be created in Scotland as celebrations kick off to mark 70 years since the passing of landmark legislation.

Events will take place across the UK’s 15 existing parks over the coming weeks, which were created in the aftermath of the National Parks and Access to the Countryside Act 1949.

But advocates insist there is still “unfinished business” in Scotland, which is home to just two designated parks – Loch Lomond & The Trossachs and the Cairngorms.

John Mayhew, manager of the Scotland National Parks Strategy Project, said the Scottish Government has so far refused to commit on the issue, citing financial constraints.

However, he insists national parks represent a relatively small investment which would generate future returns and protect world-famous landscapes, adding: “Basically, in principle, we say it is an investment and not a cost.”

He said: “I honestly think they could do it. They managed to afford the first two, and they are affording the running costs.

“There’s no denying there would have to be some Scottish Government money up front, but in many ways it would more than repay itself.”

He added: “In nearly every other country in the world, the tallest mountain is in a national park. But not Ben Nevis.”

Mr Mayhew said the two existing parks had a combined running cost of around £14 million a year – around the same as two secondary schools.

Meanwhile, all of Scotland’s mainstream political parties included references to more national parks in their 2016 manifestos, except the SNP.

He said he would like to see a new national park created north of the Border within the next five years, adding: “We have been arguing for this since 2010, so it’s been nine years already.”

Dr Calum MacLeod, policy director at Community Land Scotland, said it was crucial such schemes avoided becoming “playgrounds for urban people” at the expense of locals.

This meant getting the balance right between economic, social and environmental issues, he said.

Campaigners argue more national parks would help protect landscapes and habitats, boost tourism and the local economy and reinforce Scotland’s image worldwide.

They previously highlighted seven areas which would benefit from becoming conservation areas, including Harris in the Outer Hebrides and Ben Nevis and Glen Coe.

Efforts have recently focused on potential parks in Galloway – stretching from the Ayrshire coast to the Thornhill uplands – and the Borders, taking in an area covering Melrose and Jedburgh and down to Newcastleton.

Argyll and Bute also has tentative plans for a conservation area extending from the tiny islands of Tiree and Coll all the way to the west Kintyre coast.

Mr Mayhew said he would like to see Scottish Natural Heritage, the public body which played a key role in establishing Scotland’s existing national parks, “taking the lead” in persuading ministers more are needed.

This weekend sees the start of the Discover National Parks Fortnight, a two-week celebration which will see a number of events taking place across the UK.

In England and Wales, this includes a focus on the 1949 Act which led to the creation of the first national park in the Peak District two years later.

However, it would be half a century until separate legislation was introduced in Scotland following devolution.

Loch Lomond & The Trossachs was created in 2002 and the Cairngorms were officially declared a national park a year later.

Gordon Watson, chief executive of Loch Lomond & The Trossachs National Park, said the conservation areas offered “some of the best places in the country to switch off and reconnect with the natural world”.

He said: “Loch Lomond & The Trossachs National Park boasts some of the most spectacular scenery in Scotland, with a wide range of outdoor activities for everyone to enjoy.

“From a simple lochside stroll to climbing a Munro, there are lots of ways to get out and active and experience this special place.”

Francesca Osowska, chief executive of Scottish Natural Heritage, said Scotland’s two national parks are “amazing places which benefit our people, our economy, and our wildlife”.

She added: “With Loch Lomond and Trossachs boasting 21 stunning lochs, and Cairngorms an astounding 55 Munros, there’s so much for people to see and experience.

“Spending time in nature has been proven to have huge benefits for health and wellbeing, so we encourage everyone to take advantage of our beautiful national parks – there’s truly something for everyone.

“Our two national parks are also havens to protect Scotland’s wildlife and habitats – from ancient oaks to pine martins and ospreys.”

A Scottish Government spokesman said there are no plans to designate new national parks in Scotland.

Mairi Gougeon, rural affairs minister, said: “This fortnight gives us the opportunity to highlight and celebrate the many benefits that our two national parks bring: by protecting and enhancing our natural assets, and in the many positives they provide for health and wellbeing.”