People travelling the main highway between Otane and Waipukurau in Central Hawke's Bay have been noticing - and commenting on - the large number of black rubbish bags lining the road over the last two or three weeks.
Some have assumed the bags were being dumped there.
Others had spotted a man on a bicycle who seemed to have something to do with the proliferation of bags.
The man with the bicycle is Helmut Ruf. Helmut, visiting from Germany, has been systematically clearing the roadside of rubbish, starting from Waipawa and heading day by day towards Otane, and then towards Waipukurau.
It's not his first visit to New Zealand. He has travelled parts of the country three times before, first in 1991, by bike.
This time he came to do some house-sitting in Waipawa and, cycling from Hastings he couldn't help but notice the increase of rubbish on the roadside.
"From a car you don't notice it," he says.
"But cycling, you see it all. I was shocked."
Helmut wanted to make people more conscious of the way they were treating the landscape.
"I had a dream that we were making Mother Earth sad ... she provides us with all we need and we are not taking care of her. I hoped if I started small, it could perhaps grow and change things."
So Helmut began in Waipawa, and worked his way towards Otane.
"A dozen or so people stopped to ask me what I was doing. I was interested that they were all between maybe 50 and 65. In Germany it is the younger folk who are passionate about the environment, the older people are more complacent. I was hoping some young people might join me and take up the challenge."
His plan was to bring the bags back to where he was staying and make a huge pile ... a statement.
"I started bringing them back by borrowing my neighbours' wheelbarrow. As I got further along the highway it became impractical so I tried to carry them on my bike. That went badly and I fell off," he says.
"So I organised with my neighbour that I would leave the bags roadside and when I had a trailer-load he would use his trailer and help me collect them."
But the next day when Helmut went out, the bags were gone.
He was puzzled. More so when the following day, the next lot of bags were also gone.
"Then this guy stopped and he touched my heart. He was the one picking up the bags and taking them to the landfill. He thanked me for picking up the rubbish. I thanked him for picking up the bags."
Helmut's helper turned out to be Waipawa local Ngavii Pekepo, who was travelling to Otane most days and more than happy to get involved.
Higgins Contractors have also pitched in, sending out a crew to collect some of the bags of rubbish.
So far Helmut has collected well over 100 bags of rubbish from the roadside. Sometimes he picks up 12 to 14 bags per kilometre.
"And it's the tip of the iceberg. There's a lot more buried in the grass and the shingle.
"There are so many empty energy drink bottles ... I think they have the recipe wrong. These people don't even have the energy to take their empties to the recycling bin."
Helmut is leaving CHB shortly, but he will be passing through again next month and his dearest wish is to see that groups or individuals have stepped up to continue his cleanup work.
"And maybe then it could spread further through New Zealand."