![The first smog alert in the area the towns Essen and Dortmund were completely blocked in the inner city area for traffic about 28 years ago | Stock Photo - Alamy The first smog alert in the area the towns Essen and Dortmund were completely blocked in the inner city area for traffic about 28 years ago | Stock Photo - Alamy](https://c8.alamy.com/comp/DFKMJF/the-first-smog-alert-in-the-area-the-towns-essen-and-dortmund-were-DFKMJF.jpg)
The first smog alert in the area the towns Essen and Dortmund were completely blocked in the inner city area for traffic about 28 years ago | Stock Photo - Alamy
![The first smog alert in the area the towns Essen and Dortmund were completely blocked in the inner city area for traffic about 28 years ago | Stock Photo - Alamy The first smog alert in the area the towns Essen and Dortmund were completely blocked in the inner city area for traffic about 28 years ago | Stock Photo - Alamy](https://c8.alamy.com/zooms/6/22172c4de13e4c6b88b9ad9e52e96f9e/t7ddwj.jpg)
The first smog alert in the area the towns Essen and Dortmund were completely blocked in the inner city area for traffic about 28 years ago | Stock Photo - Alamy
![The first smog alert in the area the towns Essen and Dortmund were completely blocked in the inner city area for traffic about 28 years ago | Stock Photo - Alamy The first smog alert in the area the towns Essen and Dortmund were completely blocked in the inner city area for traffic about 28 years ago | Stock Photo - Alamy](https://c8.alamy.com/comp/DFKMH3/the-first-smog-alert-in-the-area-the-towns-essen-and-dortmund-were-DFKMH3.jpg)
The first smog alert in the area the towns Essen and Dortmund were completely blocked in the inner city area for traffic about 28 years ago | Stock Photo - Alamy
Slg. Helmut Orwat: Das Ruhrgebiet und Westfalen in den 1950er bis 1990er Jahren - Bildarchiv / Bilddatenbank LWL-Medienzentrum für Westfalen
![The first smog alert in the area the towns Essen and Dortmund were completely blocked in the inner city area for traffic about 28 years ago | Stock Photo - Alamy The first smog alert in the area the towns Essen and Dortmund were completely blocked in the inner city area for traffic about 28 years ago | Stock Photo - Alamy](https://c8.alamy.com/zooms/6/0365b935c92746d3909bf490e2dd3e08/t7de27.jpg)
The first smog alert in the area the towns Essen and Dortmund were completely blocked in the inner city area for traffic about 28 years ago | Stock Photo - Alamy
![The first smog alert in the area the towns Essen and Dortmund were completely blocked in the inner city area for traffic about 28 years ago | Stock Photo - Alamy The first smog alert in the area the towns Essen and Dortmund were completely blocked in the inner city area for traffic about 28 years ago | Stock Photo - Alamy](https://l450v.alamy.com/450v/dfkmk5/the-first-smog-alert-in-the-area-the-towns-essen-and-dortmund-were-dfkmk5.jpg)