Thom57: All cities are dirty, some more than others. I lived in NYC for three decades and it went from dirty to filthy as population grew and public sanitation budgets withered. As you may know, I currently live in Shanghai, China and it is the cleanest city I have ever witnessed. With a city population of 24 million people it takes a huge public budget to employee the tens of thousands of sanitation workers who sweep the streets around the clock and the restroom employees who clean each public toilet, often after every use. And not all areas of the city are equally clean; just like US cities, more public resources are spent cleaning the business and tourist areas, while allowing the areas inhabited and frequented by the poorer, local residents to accumulate more filth before action is taken. Yesterday I arrived in Seattle, and as clean as Shanghai is, it is good to be home.

Question: Which city would you say is the cleanest one?