For the more information about the air resources of the National Park Service, please visit http://www.nature.nps.gov/air/.
Ironsides Island is a glacially-scoured granite knoll. The site's most significant feature is the breeding colony of great blue herons.
Year designated: 1967
Please remember, National Natural Landmarks (NNLs) are not national parks. NNL status does not indicate public ownership, and many sites are not open for visitation.
Last Updated: June 28, 2012