Eureka is a city located in St. Louis County, Missouri, between St. Louis and Pacific along Interstate 44. As of the 2000 census, the city had a total population of 7,676. It is two miles west of the former site of Times Beach, the site of dioxin contamination discovered in the 1980s; the area was cleaned up and became Route 66 State Park. Since 1971, Eureka is best known in the region as the home of the amusement park formerly known as Six Flags Over Mid-America and now called Six Flags St. Louis.