The most expensive zip codes in 15 major US cities

City life is expensive - but city life in the swankiest neighborhoods in the US can be outrageous.

The median listing price for homes in the quaint Boston neighborhood of Beacon Hill is over $3.7 million. And if you head to Atherton in San Francisco, the median home price exceeds $10 million.

Online real estate site Trulia analyzed the median price per square foot of homes across the biggest metropolitan areas in the US and provided Business Insider with a list of the most expensive zip codes in each.

Here, we've highlighted the most expensive zips in 15 major cities, ranked in order of price per square foot of real estate, the neighborhood (or island) they're most closely associated with, and the median listing price in each neighborhood.