Marco Island is a city and barrier island in Collier County, Florida, 20 miles (32Â km) south of Naples on the Gulf Coast of the United States. It is the largest barrier island in Southwest Florida's Ten Thousand Islands area, which extends southerly to Cape Sable. Marco Island is home to an affluent beach community with resort amenities.
Marco Island is a principal city of the Naples–Marco Island Metropolitan Statistical Area. The population was 15,760 at the 2020 census, down from 16,413 at the 2010 census. The population more than doubles during the winter.