Finding free parking in Washington, D.C. is difficult but possible if you know where to look. Most metered parking is free on Sundays and on major federal holidays like New Year's Day, Juneteenth, and Christmas. In residential neighborhoods, many streets offer two-hour free parking for visitors, but you must be careful not to stay longer or park in "Permit Only" zones, as enforcement is aggressive. Another "secret" for free parking is at WMATA (Metro) stations; parking is free at Metro-operated lots and garages on weekends and federal holidays. During the week, some areas near the National Arboretum or portions of Rock Creek Park offer limited free parking lots. For overnight stays, most metered spots are free from 6:30 PM (or 10:00 PM in some zones) until 7:00 AM the following morning. Always read the signs carefully, as "No Parking" during rush hour or street cleaning hours can lead to an immediate tow, costing hundreds of dollars in fines.