They are as follows...
|3. ||Helsinki, FI|
|6.||Oslo, NO ||Stockholm, SE||Zurich, CH|
|9. ||Katsuyama, JP|
|10.||Bern, CH||Montreal, CA||Vancouver, CA||Boston, US|
|Lexington, US||Pittsburgh, US||Nürnberg, DE||Geneva, CH|
|18.||Auckland, NZ||Wellington, NZ|
|21.||Amsterdam, NL||Toronto, CA|
|23.||Lyon, FR|| |
|24.||Copenhagen, DK |
|25.||Kobe, JP ||Omuta, JP|
Canadian cities live up to their reputation for being clean. Not only was Calgary (below) first but there are 5 Canadian cities in the top 25. But there were also 5 American cities.