In Atherton, Calif., 94027, the most expensive home currently on the market is a 12,840-square-foot Mediterranean mansion with a $21.988 million price tag. Not a millionaire? Good luck finding a place to live in this Silicon Valley enclave. The least expensive home for sale in the 94027 ZIP code is a 1,370-square-foot, two-bedroom, two-bath bungalow. In other words, a starter home–with an asking price of $1.499 million.

The median price of the 24 homes listed for sale over the summer was $9.03 million, making Atherton the most expensive ZIP code in America for the second year in a row.

“Atherton is drawing a lot of young executives: CIOs, CFOs, and CEOs,” says Ken DeLeon, a Silicon Valley broker whose firm, DeLeon Realty, has $480 million in sales closed or pending to date this year. “And the international buyers really draw on the prestige.”

For Silicon Valley’s wealthy, Atherton offers proximity to the area’s tech start-ups as well as its big public companies, including Apple in Cupertino, and Facebook and Google in Mountain View. Another advantage over prestigious, yet further out areas (such as Woodside, home to billionaires Larry Ellison of Oracle and Scott Cook of Intuit) is Atherton’s relatively relaxed building regulations. “If you drive up and down Atherton Avenue all you see are huge construction, 12,000-square-foot homes,” DeLeon says. Younger, tech-rich buyers who want a more urban feel like that Atherton is just minutes away from downtown Menlo Park and Palo Alto, DeLeon says.

But Atherton 94027 is the only Bay Area ZIP—or California ZIP code, for that matter–to crack the top 10 on our 2014 list of America’s Most Expensive ZIP Codes. This year New York City dominates the list, with six ZIP codes among the top 10. Long Island’s Sagaponack 11962, in the town of Southampton, grabs the No. 2 slot, followed by three consecutive New York City ZIPS: Lower Manhattan’s 10013 (No. 3), the Upper East Side’s 10065 (No. 4) and 10075 (No. 5).

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