Park · Virginia
Leashed dogs (6ft) on every trail, at the overlooks and in the picnic areas. They may not enter the Potomac from anywhere in the park — the current here kills people.
The Potomac dropping seventy-six feet through a rock gorge fifteen miles from the capital, with overlooks a short walk from the lot.
The policy above is the standing rule of the agency that manages this land, as published on its own pages. Official page.
Rules change, and seasonal beach rules change twice a year. Check before a long drive.