The 6.29-acre Glen Oak Forest Preserve in Glen Ellyn features woods and a small prairie.
Glen Oak contains restored prairies, reforested areas and floodplains and a variety of native sedges, rushes and knotweeds. It's home to several types of birds, including breeding great blue herons, American goldfinches and killdeer, and ecologists have spotted brown thrashers, sora rails and other rare birds here as well.
Glen Oak is north of Route 53 and east of Spring Avenue. It does not have a parking lot.