New money pours into California wine country

Here's what $32M gets you in Sonoma County

Think real estate is crazy in Silicon Valley? Try wine country.

In Sonoma County, which is about two hours north of San Francisco, luxury listings—meaning those homes priced north of $1 million—are up nearly 90 percent year over year, according to Sotheby's.

Brokers attribute that surge, in part, to tech millionaires pushing up prices.

"Because of the success of so many start-up firms in San Francisco, there's a lot of money that is being manufactured in the area," said Chuck Lamp of Sotheby's International Realty. "And a lot of it is going into real estate."

Megan Hawkins | CNBC

The most expensive home on the market right now is a 20,000-square-foot estate created in the style of an Austrian countryside villa. The property, which rests on 600 acres, boasts five bedrooms, 12 bathrooms, a home theater and an infinity pool.

The price: $32 million.

The estate is owned by Ed Kozel, former chief technology officer of Cisco Systems. He also was on Yahoo's board for nearly a decade.

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In fact, buyers have their pick of megamansions in the area. There are now more than half a dozen homes on the market priced at $25 million or higher.

"This market has become the second home destination of choice for wealthy techies and international investors who have already made purchases in Silicon Valley," said Ken DeLeon of Palo Alto-based DeLeon Realty, which is on track to do more than $600 million in sales this year.

"These buyers want to expose their portfolio to the weekend getaway homes in Sonoma and Napa," DeLeon added.

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The question is whether Kozel can find another tech heavyweight to purchase his estate. There are already several prospective buyers in Silicon Valley, according to Lamp.