Cool maps showing the segregation of various cities.
Well, that explains a lot. Detroit is an extremely racist city and has been going back to at least World War II.
Segregation is everywhere, but some places it's more complex. Here's San Antonio:
San Antonio looks segregated too, but if you click on the larger version of the map, you can see that in fact there are lots of Latinos (yellow) in the white (red) neighborhoods and the other way around to some extent.
Anyway, it's all really fascinating.