is a village in Lake County, Illinois, United States. The population was 6,670 at the 2000 census, and it is the northernmost city in Illinois. Winthrop Harbor's main claim to fame is North Point Marina. With moorage over 1,500 boats, it is the largest marina on the Great Lakes. Nearly one million visitors take advantage of the marina, its associated beaches and other recreational facilities every summer.
As of the census of 2000, there were 6,670 people, 2,370 households, and 1,884 families residing in the village. The population density was 1,548.0 people per square mile (597.5/km²). There were 2,435 housing units at an average density of 565.1/sq mi (218.1/km²). The racial makeup of the village was 93.79% White, 0.57% African American, 0.49% Native American, 1.90% Asian, 0.01% Pacific Islander, 1.51% from other races, and 1.71% from two or more races. Hispanic or Latino of any race were 4.54% of the population.
There were 2,370 households out of which 40.1% had children under the age of 18 living with them, 66.8% were married couples living together, 8.4% had a female householder with no husband present, and 20.5% were non-families. 17.0% of all households were made up of individuals and 5.1% had someone living alone who was 65 years of age or older. The average household size was 2.81 and the average family size was 3.17.
In the village the population was spread out with 27.4% under the age of 18, 8.1% from 18 to 24, 31.2% from 25 to 44, 25.2% from 45 to 64, and 8.1% who were 65 years of age or older. The median age was 36 years. For every 100 females there were 100.4 males. For every 100 females age 18 and over, there were 97.8 males.
The median income for a household in the village was $72,795, and the median income for a family was $79,442. Males had a median income of $44,795 versus $32,392 for females. The per capita income for the village was $24,256. About 1.9% of families and 3.1% of the population were below the poverty line, including 3.1% of those under age 18 and 4.2% of those age 65 or over.