At the start of the new year, i.e. as of January 1, 2008, the new environmental zones go into force first in the three designated cities of Berlin, Cologne and Hannover and only vehicles displaying a special emissions-control sticker ("Feinstaubplakette") will be allowed to enter these zones. This sticker will be valid throughout Germany.
The special emissions sticker comes in three colors: red and yellow and green. From January 1, 2008 to January 1, 2010, vehicles having stickers in any of the three colors (such vehicles at least meet the requirements of Pollutant Class 2) can drive in the environmental zone. After January 1, 2010 only vehicles with the green sticker (Pollutant Class 4) will be allowed to drive in the environmental zone.
At the official website of Berlin, there is a map of the affected area of the city also showing the "environmental zone" traffic sign which will mark the designated area in Berlin (the smaller "sticker sign" below the larger sign shows which stickered cars can pass the sign - and, obviously, cars having no such sticker can not drive in these areas - unless they obtain a special exemption):
The Berlin city website also provides downloads in five languages of the applicable rules and affected areas as follows:
Umweltzone Broschüre (pdf; 192 KB) - German
The environmental zone (pdf; 192 KB) - English (Better Air for Berlin - What Drivers Need to Know)
Cevre Koruma Bölgesi (pdf; 335 KB) - Turkish
Экологическая зона (pdf; 1.8 MB) - Russian
Strefa ekologiczna (pdf; 345 KB) - Polish
There is also a special website for the environmental zone in Cologne (Köln), at which a special Flyer in German language, but including a map of the environmental zone can be downloaded. The map below is linked from meinestadt.de (which contains additional information in German):
Also Hannover has a special website page for its environmental zone and a large map of that zone, which we link to here in smaller format:
Environmental zones. Absurdly rising oil and gas prices. Pressures from the EU on German car manufacturers. Perhaps it is no wonder that domestic cars sales in Germany in 2007 have been disastrous thus far. It may be getting time to break out the bicycles.