Meet 'Thomas On The Mountain,' a lazy wooden giant happily reclining near the Copenhagen suburb of Albertslund.

Thomas is one of six giant sculptures crafted by self-described recycling artist Thomas Dambo and hidden in the woods around the Danish capital. It's all part of a project called 'Forgotten Giants'.

All six sculptures were made completely from local scrap wood and recycled materials.

"When I'm working in my workshop, I get a lot of scrap wood from all my recycled materials that I've built from, and I was thinking as a true recycle artist I should be able to utilise all these smaller pieces of scrap," explains 37-year-old Dambo.

"So, I start digging into, experimenting about what could I create from my own scrap and that led me on this path to create these big sculptures that are made from smaller pieces of scrap wood."

Rather than exhibiting his towering creations in an art gallery, Dambo decided to hide his giants in picturesque public locations around the outskirts of Copenhagen.

The only clue to where to find them is a cryptic map posted on the artist's website and a riddle placed nearby.

It's an attempt to send art fans on an open-air sculpture treasure hunt, and perhaps also discover some hidden nature spots along the way.

'Little Tilde' is placed near a small lake, timidly glancing between the trees. Dambo also built 28 birdhouses inside the sculpture.

"I wanted people to go and investigate the city that we live in," explains Dambo.

"I think a lot of people they live like in a triangle on the road between their home and their job and their supermarket and then they repeat around in that triangle. And people really seldom go outside those roads on that triangle.

"But I think a lot of the adventure in our lives lays on the other side of the fence, or the wall, or the road.

"But sadly a lot of people think they have to go on vacation on the other side of the planet to see something new, but the matter of fact is there's so much stuff that we haven't seen in our own city and there's a lot of beautiful nature even inside a big urban environment like Copenhagen."

Each giant is designed specifically for the location.

'Thomas' reclines on the side of a steep hill admiring the view. He's named after an intern that worked with Dambo on the project.

'Sleeping Louis' is hidden in a small clearing on top of a hill. People can crawl inside his mouth and even sleep inside the sculpture.

"I always try to make them fit into the environment," says Dambo.

"So if there's a little hill, maybe laying up or leaning against the hill, or to make them part of nature and part of where they are instead of putting them on top of a pedestal that I believe makes a sculpture a little bit more dead because you understand it's a sculpture.

"But just by making it lay like I would lay in the grass or the giant just laying in the forest like that it gives it more life and spirit I believe."

The project has become a hit among Copenhagen locals and families looking for a fun adventure. And there are no plans to take them down.

"I think it's awesome," says 41-year-old Albertslund resident Lasse Tassing, who's taking his two daughters for a walk.

"I mean, you go find them, you can't find them on a map, and so it's a great way to go out in the nature and really explore the woods. And they're made from recycled wood, I think that's amazing.

"We have a generation of young people with iPads and phones and what not, they don't venture out as much as I used to do when I was a kid, so I think it's a great way to engage people in nature again."

But there's a serious side too. Dambo hopes that by crafting fun sculptures from recycled materials he can demonstrate the potential in materials often discarded or forgotten.

"I think that it's really important that we take care of our planet because there's one planet and I think it makes no sense to go all of the way to the other side of the world and then cut down some trees in the rain forest and then make them into some wooden product that you only use one time for ten minutes for chop sticks or something like a palette or something and then just throw it away," he says.

"I think all these materials, there's so much more potential in all these materials than just discard them in a landfill or burn them in an incineration plant."

A fun way to tackle a giant problem.