Dec. 22, 2 p.m. to 4 p.m., Gunpowder Falls State Park, 10500 Belair Road, Perry Hall. Celebrate the shortest day of the year with an evening hike guided by a park ranger. This three-mile rugged hike is through rough and varied terrain. Bring your own headlamp or flashlight, water, and dress appropriately. Pre-registration is required. Call: 410-592-2897. Donations welcome.