The field was filled with thousands of dancing people was free of garbage and green as a garden. There were cigarette butts, no wine corks, no torn tissues littering the grass. The conspicuous absence of waste at the NorthSide music festival is not just a matter of chance; there is an orderly system behind the cleanliness. Making the rounds through the dancing masses are so-called Trash Talkers adorned in neon yellow vests.

The NorthSide festival in Aarhus, Denmark's second-largest city, is the biggest open-air music festival in the country; its organizers place a lot of value on the sustainability of the three-day outdoor party, held this year from June 17-19. It's a subject that many event organizers have taken up in recent years.

"There's a strong social consensus today that we need to think about protecting the environment and think about future generations," said Holger Schmidt from the Sounds for Nature organization which deals with sustainability management at outdoor concert events. "Many festivals in northern and central Europe already have high standards. Some German events could catch up to them."

Experience music live and give back to the community

The most transparent problem at festivals where people can camp is the mounds of garbage that are left behind at the end of a fun weekend. It's not only food waste but also often tents and tarps, lawn chairs and camping stools, as well as clothing. For that reason, the Hurricane music festival in northern Germany, taking place from June 24-26, is working together with the group Hanseatic Help.

"Any of the camping provisions that are still in good condition will be gathered by volunteers and donated to organizations in Hamburg that could use the equipment," said sustainability spokesperson Julia Baer.

Besides projects that benefit the environment are programs with a strong social aspect. "It's about giving back to the community and perhaps also sending a political message," said Holger Schmidt.

One example of this comes from the twice yearly Tollwood Festival in Munich which took place last winter with the refugee crisis as a guiding theme. The 10,000 Hours initiative in Holland tries to get music fans to commit to a volunteer project whenever they purchase tickets for an electronic music festival. Foodsharing is also playing a larger role at festival sites today, as they seek to reduce food waste by distributing edible leftovers.

Not everyone has a taste for a vegetarian festival

Every event faces its own unique challenges in trying to put on a sustainable festival. The organizers of the Way Out West festival in Sweden have determined that the greatest emissions culprits are food preparation and catering, which is why they decided to completely eliminate meat products from their menu. "Such a decision isn't something that every member of the public is willing to put up with. That's why it's important to be creative within your means and start new projects," said Schmidt of Sounds for Nature.

Visitors to the Hurricane festival that take especial steps to behave sustainably can win a bag made of old festival posters. You can gather points for traveling by train or collecting a sack of trash or by camping in the Green Living area for free. "We want to make people more aware of the environmental protection theme," said Julia Baer.

Nevertheless, it's not that easy to sensitize people to such ecological questions when they are taking a break from their everyday lives and have set out to enjoy their free weekend at a festival, according to Schmidt.

Pack up the car and head out

In reality, traveling to the festival site by car is often the largest contributor to environmental damage, even when it's invisible compared to the mounds of trash that pile up. That's why Schmidt says a cooperation with the German train service, Deutsche Bahn, would be desirable.

Wacken Open Air, with over 80,000 visitors, is one of Germany's largest music festivals

"At the same time, that requires a different way of thinking for festivalgoers who could no longer pack an overflowing suitcase."

It's also not something that is possible at every festival, since many are held in out-of-the-way locations. "For a large event like Wacken Open Air, which is in the flatlands, it is much more difficult to get there more efficiently than it is to get to NorthSide in the center of Aarhus," commented Schmidt.

For the Danish festival organizers, the sorting and recycling of garbage is an important element, as they want to set a standard. Denmark is, after all, the country with the greatest amount of household garbage per person when compared to other EU countries.

Finding the right balance between having fun and being responsible is not easy, as the top priority for event organizers is to offer an unusual concert experience. For Schmidt, at least one thing is clear: "There's no such thing as an emission-free festival."