The nation’s largest and most historically prominent cities tend to have highly educated sectors among their populations, and within those cities, certain ZIP codes – which generally don’t correspond to town or city boundaries – have concentrations of college graduates and those holding advanced degrees.

Using census data, 24/7 Wall St. determined the percentage of adults 25 years and over in ZIP codes across the country with at least a bachelor’s degree. Not surprisingly, it found that Washington, D.C., Boston, Chicago, San Francisco, and New York all had numerous ZIP codes ranking among the top 50 for college grads, making them among the best educated towns in the country.

However, the country’s most educated ZIP codes aren’t necessarily located in or around those cities. In fact, 22 of the top 50 are not within striking distance of the 10 cities with the highest percentage of college graduates – and of those 10 cities, only four (San Francisco, Washington D.C., Atlanta, and Boston) include or are near ZIP codes that are among the most educated in the country. 

Click here to see America’s most educated ZIP codes
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While higher education is certainly associated with higher incomes, the percentage of college-educated residents in a given location is not as strong an indicator of wealth as might be imagined. A postgraduate degree strengthens the correlation. One ZIP code in Boston can boast of great erudition, with 94.6% of its population holding undergraduate degrees – the highest percentage in the country – and 33.7% having earned an advanced degree, but its median household income is only $57,989. (See how the U.S. compares to the most educated countries in the world.) 

At the same time, one ZIP code in San Francisco ranks a relatively modest 50th in college education (with 85.2% of the population having a bachelor degree and 50.2% holding graduate degrees) – but the median household income is $250,000, the highest in the country.