The object of this quiz is to click on the circle containing the largest population. When you begin you'll be shown 2 circles on the map with radii between 10 and 250 miles which do not intersect. Click on the one with the larger population within it (based on US census tract info) then 'Submit' - if you are correct you'll move on. One incorrect round and the quiz is over. Every 5 rounds the number of circles on the map will increase by 1. Try to build the longest streak of correct circles. Circles displayed will always be non-intersecting.
NOTE: You may have to zoom out to see all circles, occasionally a AK/HI circle will be included. Also, only population within the US is included in the total, any Canada/Mexico coverage counts as 0 population within the circle.
Quiz Takers 
This quiz proves that excluding CDPs from regular city quizzes in places like Maryland and Nevada essentially leaves those states almost completely empty.
Yeah but in some states even with CDP’s you don’t get all places – states like Alabama both cities/towns and CDP’s don’t cover the entire population of the state.
It comes down to the urbanization percentage of the state. In theory, if you add up all the cities and CDPs and divide the total by the state’s population, you should get a number close to that percentage.
The census data for Maryland does largely account for their urban populations. The thing that makes it stand out is the sheer percentage of its urban population that reside in CDPs (70%). The only other state that comes close to that percentage is Hawaii, which is of course 100% CDPs.
The Census Bureau states that CDPs are supposed to be “the statistical equivalents of incorporated places” as a way of generalizing the concept of city along the lines of “if it looks like a duck and quacks like a duck…”
I’m not saying it would be better if CDPs were included for every state. But if you’re going to include Hawaii’s, then you may as well include MD’s as well because the only practical difference between it and HI is that it also happens to have a handful of cities.
Nevada’s CDP percentage is also fairly high (40%), but if you were to include just the four huge CDPs in Clark county that have ~200K+ people (Paradise, Enterprise, Spring Valley and Sunrise Manor) then the statewide CDP percentage would drop to just 12%. But I guess you do count them in the Las Vegas metro quiz so it’s all good.
Since New England and New Jersey are almost entirely covered by municipalities covered in your city quizzes, shouldn’t their CDPs be excluded like Hawaii, since those places are already included in the town they’re in? I don’t think it makes sense for those places to show up in both types of quizzes.
I’m going to leave those ones, they are separate CDP’s and towns so the CDP’s are not technically included in my cities quizzes.
I am honestly surprised at the number of large CDPs in Maryland.
Certain metro areas seem to be heavy on the CDPs, too, namely Las Vegas, LA, the alluded-to Washington-Baltimore area and pretty much any metro area in Florida. Those are the keys to a good score, I think.