In a vote in which you would think somewhere like Detroit would be selected, Louisiana's Crescent City has been voted as America's Dirtiest City. This probably comes as no surprise to most people. Just walk out of your favorite, or I should say, any bar on Bourbon Street and take a nice, deep breath through your nose. By any means, NOLA is not the cleanest city, but definitely the most fun in my opinion. Coming in at number 2 is Philadelphia. Other cities in the top 10 are Detroit and Los Angeles. Houston rounded out the top 10.