Marietta Real EstateMarietta is located in Illinois. Marietta, Illinois has a population of 82. Marietta is less family-centric than the surrounding county with 16.67% of the households containing married families with children. The county average for households married with children is 24.56%. The median household income in Marietta, Illinois is $45,000. The median household income for the surrounding county is $53,441 compared to the national median of $69,021. The median age of people living in Marietta is 40.5 years. Marietta WeatherThe average high temperature in July is 85.7 degrees, with an average low temperature in January of 15.4 degrees. The average rainfall is approximately 38 inches per year, with 19 inches of snow per year. Marietta MapReal estate near MariettaNearby CitiesNearby Cities Homes for Sale |