Although both are waterfront cities, something besides the salt water separates La Jolla, Calif. on the Pacific Ocean from Sioux City, Iowa on the Missouri River — like a $1.7 million dollar difference in the cost of homes, according to a study released Tuesday morning. In an annual comparison of similar homes in 315 U.S. markets, La Jolla topped the chart as the most expensive real estate market in the nation with a $1,841,667 average home price. Sixteen hundred miles away in America’s heartland sits Sioux City, the most affordable real estate market in America, where a similar home would cost $133,459, the study found. The study, released by real estate brokerage Coldwell Banker, compares the cost of similar 2,200 square foot, four-bedroom, two-and-a-half bath homes in 315 markets across the United States. See more study results. La Jolla and Sioux City are not alone in representing California and the Midwest, either. In fact, eight out of ten of the country’s most expensive housing markets are in California, according to the study, and eight Midwestern cities make the list of the nation’s 10 most affordable home markets. “This year’s study comes at an interesting time in our nation’s history with the impact of the housing correction and mortgage financing serving as critical economic issues in the presidential election,” said Jim Gillespie, president and chief executive officer of Coldwell Banker Real Estate. The cumulative average sales price of the four-bedroom homes surveyed in the 315 U.S. markets covered in the Coldwell Banker HPCI was $403,738, a 4.4 percent decline from the $422,343 reported one year ago. La Jolla edged out perennial most-expensive contender Greenwich, Conn. ($1,787,000) and other West Coast markets as the most expensive U.S. market in the study, which should be telling; the housing mess has been centered in California. Beverly Hills was the most expensive studied in the U.S. market last year at $2.21 million, Coldwell Banker said; the study does not include Manhattan, however, citing a lack of relevant data. The Northeast Corridor (from Maine to Washington, D.C.) and California dominate all but five of the most expensive “top 40” U.S. markets slots, according to the study — with just one town from those regions (Augusta, Maine) appearing among the top 40 most affordable markets. Texas, led by Arlington, has six of the study’s 40 most affordable markets. For more information, visit http://www.coldwellbanker.com.