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The 10 Cleanest Cities

Cities are not exactly synonymous with cleanliness; so how to determine which are the closest to that ideal? Ireland and Australia have their annual Tidy Town competitions, but it takes more than an attractive square and an effective anti-litter campaign for large metropolitan areas to be considered tidy.

Each year, the consulting, outsourcing and investment firm Mercer ranks cities worldwide in its Quality of Living Survey. The 2010 survey crunched data from 221 cities. Drawing from this data, Mercer also compiles an eco-ranking of the cities, taking into account water availability and drinkability, waste removal, sewage systems, air pollution and traffic congestion. Coming in at the bottom of that list were Muscat, Oman; Point-a-Pitre, Guadeloupe; and worst of all were Nagoya and Osaka in Japan, and Frankfurt, Germany in a three-way tie for last.

Now click ahead to see the ten cities that get it right: in descending order to No.1, the 10 Cleanest Cities worldwide.

By Colleen Kane
Posted 29 Dec 2010

Bob Stefko | Getty Images