Atherton, Calif., is America's richest place for the third year in a row. Its residents made an average of $450,696 in 2017, a $7,293 increase from the prior year, according to the annual Bloomberg Richest Places index.
Medina, west of Minneapolis, made its debut in the top 100.
Billionaires who have called Atherton home include Google's Eric Schmidt and Facebook's Sheryl Sandberg. Both Google and Facebook have headquarters within 10 miles of Atherton, which is nestled inside the nation's tech hub dubbed Silicon Valley. Stanford University is just 2 miles down the road from the town.
Atherton Mayor Bill Widmer said the tree-lined streets and lot sizes of at least 1 acre offer the residents privacy.
"We value a semi-rural environment," said Widmer, who moved to Atherton in 1996. "There are few sidewalks and many places don't have streetlights."
Scarsdale, N.Y., a wealthy suburb north of Manhattan, moved up to the No. 2 spot on this year's list as its residents enjoyed a $30,000 increase, on average, in annual household income from the prior year, pushing Cherry Hills Village, Colo., to the No. 3 spot. Top school districts are one reason why residents choose to live there.
"We moved here as many did because of the outstanding school system," said Scarsdale Mayor Dan Hochvert, a 40-year resident. "That is one of the primary drivers."
Accessibility to a city center is also a key characteristic of all three. Just as Atherton is accessible to San Francisco and Scarsdale is a train's ride away from New York City, Cherry Hills Village is a 15- to 20-minute drive to both downtown Denver and the city's tech center.