Putting a value on the Welsh countryside
For the first time a groundbreaking report has put a value on the economic benefits of the UK's parks, lakes, forests and wildlife.
But can you put a price on your favourite view, a walk in the woods or the area of Wales you live in?
My journey starts in Montgomeryshire where there are plans to construct a 19-acre substation and 100 miles of pylons to connect wind farms to the National Grid.
Dairy farmer and chair of the Montgomeryshire Against Pylons campaign, Jonathan Wilkinson, says the impact would be devastating.
"It's only now the area is under threat that we realise how priceless it is. It's beyond value. If this development went ahead it would overwhelm the village. It's difficult to see how the community could survive it."
However, according to the National Ecosystem Assessment, the environment in Wales as a whole contributed £9bn of goods and services to the Welsh economy and supports one in six jobs.
But how do we value an area? I went to Newborough Forest, on Anglesey to meet Prof Gareth Edwards-Jones, one of the report's authors.
"There are three types of value we place on our environment. Direct use, indirect use and non-use.
"It is easy to work out what food and timber are worth to the environment, but harder to work out the value of things like the red squirrels here in Newborough Forest. We value them but we do not use them.
"So we ask people what they would contribute to a trust fund to protect them and then calculate a total."
For Rob McBride, the environment transformed his life. He worked as a software engineer in Wrexham for 22 years before ill health meant he had to make some drastic life changes. He now walks around the UK recording ancient trees for a Woodland Trust campaign. I went to Chirk to find out more.
"In 2004 I had to leave my job as I was suffering from severe anxiety and depression. I started volunteering for the Woodland Trust and being outdoors has given me hope and saved my life in a way.
"The campaign is to record the ancient trees and lobby the government to protect them. At the moment they can easily be chopped down even though they are our living history."
Can Rob put a value on the ancient trees?
"You can't put a price on them. Fernando Torres was worth £50m and they're worth 50 of him at least."
In reality, according to the National Ecosystem Assessment, forests contributed £429m to the Welsh economy.
However, Prof Edwards-Jones says we need to do more to get people out and about using the countryside.
Which is exactly what Forestry Commission Wales are trying to do at a site in the south Wales valleys.
The next step on my journey was to Gethin Woods, on the edge of Merthyr Tydfil, to meet forest district manager Dai Jones.
"We are going to build a mountain bike centre and trails in the wood. People don't use the woodland as much as we'd like, but we hope this will encourage them.
"We also hope it will transform the image of the valleys - people will go away thinking it's a green and verdant place, rather than with the outdated image of the dreary valleys.
"If we can change that view - it's valueless."
Priceless and beyond value - it seems the people I have spoken to cannot put a price on their natural surroundings despite what the National Ecosystem Assessment reports.
So in our green and pleasant countryside, things are rarely black and white. Its value, much like its beauty, lies in the eye of the beholder. But one thing I've learnt on my journey is that across Wales, people will continue to fight for what they hold dear.
Eye on Wales is broadcast at 1305 BST on Sunday 19 June on BBC Radio Wales.