From Harford County government:
The Harford County Department of Parks and Recreation will make exterior renovations to the Eden Mill Park’s Historic Grist Mill. Due to these renovations, the mill portion of the site will be closed to tours starting July 21, 2014, for approximately four months.
The Nature Center, as well as, all other camps and activities will continue as scheduled at the park.
If you have any questions, please call the Eden Mill Nature Center and Park at 410-836-3050.