The Winter Olympics in South Korea have fueled hopes for a rapprochement between North and South Korea. But, as with almost all Olympic Games in recent years, environmental problems are also coming to light. Conservationists complain that the sports spectacle leaves irreparable damage to the environment.

For the Olympic downhill track in Jeongseon, tens of thousands of trees had to be cut down. Environmentalists were up in arms: Wangsasre birches had been there for more than 500 years, and served as a refuge for protected animal species. The activists speak of a "chainsaw massacre." Ironically, there isn't even snow in the area — artificial snow has to be used.

By the time the Winter Games roll around, you need snow — there is no way around that. If there is none around, organizers get snow cannons ready to cover all slopes with artificial snow. That's how it's done in Pyeongchang, because conditions there are anything but ideal for skiing. The region is on the same latitude as Sicily and has no high mountains. Winters are cold, but dry.

The Olympics in Sochi, Russia, had a higher environmental impact than any other Games, environmentalists have said. Deforested mountains, heavy equipment brought into nature reserves — the entire region became a construction site. For decades, the International Olympic Committee has been committed to environmental protection, but in Sochi, many critics say, no one paid attention.

Wherever construction takes place, debris is sure to pile up. Rubble accumulated around Sochi, and according to activists, it was simply dumped into quarries and former nature reserves. Ordinary garbage piled up as well and made its way into water conservation areas. Residents complained that they ran out of drinking water.

At the Summer Games in Brazil, water-sports athletes feared for their health. The sailing competitions took place in Guanabara Bay, referred to by many as the "Cesspool." The water was filthy and full of pathogens, critics said. Even now, a year and a half after the Olympic event, environmentalists say little has changed. The difference is that the world knows about it now.

The Beijing Summer Olympics made the extremely high air pollution in China a topic of conversation the world over. In the months and even days leading up to the Games, there was a thick haze over the Olympic stadium. The top floors of Beijing's skyscrapers could hardly be made out through the smog. Doctors warned of respiratory problems for athletes.

The next summer Games will take place in Japan. In 2017, the water quality in Odaiba Marine Park was examined - this is where swimming and triathlon competitions will be held. The analysis found an unusually high concentration of bacteria. Organizers in Tokyo blamed the high amount of rainfall for bringing pollutants into the bay.