It is the home of Northern Michigan University.
The city was originally named New Worcester, after Worcester, Massachusetts.
Marquette is the sister city of Kajaani, Finland and Yokaichi, Japan.
The area in and around the city is the legendary home of the Marquette Monster, which is depicted at the top of the Old City Hall plaque.
According to the United States Census Bureau, the city has a total area of 50.2 km² (19.4 mi²). 29.6 km² (11.4 mi²) of it is land and 20.6 km² (8.0 mi²) of it is water. The total area is 41.09% water.
As of the census of 2000, there are 19,661 people, 8,071 households, and 4,067 families residing in the city. The population density is 665.3/km² (1,723.9/mi²). There are 8,429 housing units at an average density of 285.2/km² (739.1/mi²). The racial makeup of the city is 95.04% White, 0.82% African American, 1.74% Native American, 0.82% Asian, 0.02% Pacific Islander, 0.22% from other races, and 1.33% from two or more races. 0.77% of the population are Hispanic or Latino of any race.
There are 8,071 households out of which 23.0% have children under the age of 18 living with them, 37.2% are married couples living together, 10.2% have a female householder with no husband present, and 49.6% are non-families. 37.0% of all households are made up of individuals and 11.5% have someone living alone who is 65 years of age or older. The average household size is 2.13 and the average family size is 2.81.
In the city the population is spread out with 16.8% under the age of 18, 25.9% from 18 to 24, 23.8% from 25 to 44, 19.7% from 45 to 64, and 13.8% who are 65 years of age or older. The median age is 31 years. For every 100 females there are 94.4 males. For every 100 females age 18 and over, there are 92.4 males.
The median income for a household in the city is $29,918, and the median income for a family is $48,120. Males have a median income of $34,107 versus $24,549 for females. The per capita income for the city is $17,787. 17.0% of the population and 7.2% of families are below the poverty line. Out of the total people living in poverty, 12.3% are under the age of 18 and 5.1% are 65 or older.