F. The public's opportunity to appreciate and enjoy the rich variety of the Basin's landscape is hampered now by a shortage of suitable routes designed to furnish that opportunity. Two systems of such routes would link together the Basin's most fundamental attractions and connect it with the amenities of other regions: 1. Studies are already well advanced toward the definition of needs for recreation and scenic motoring tied in with the existing George Washington Memorial Parkway, Skyline Drive, and Blue Ridge Parkway. They should be completed and implemented when feasible in consultation with the Department of Transportation. A route that warrants equal consideration would be the extension of the George Washington Memorial Parkway from Mount Vernon to Yorktown as recommended in the _Potomac Interim Report to the President_. 2. A Basinwide system of trails for hiking, bicycling, and horseback travel has been studied and its details are presented in a separate report. This compatible and organic means of putting town and city people in touch with the natural environment and the countryside is an indispensable element of a full recreational program for the Basin, and it is strongly to be hoped that the establishment of the Potomac Heritage Trail along the river and the protection of the ridgeline Appalachian Trail--the two trunk elements of the system--will be promptly achieved under the legislation recently acted upon by the Congress. G. Some of the most basic beauty of the Potomac Basin is found in its older towns and its inhabited countryside, where centuries of history are reflected in structures, historic sites, and types of land use. To protect this beauty and richness against unnecessary destruction and degradation, vigorous action is indicated: 1. The Basin States should consider the possibility of utilizing their State Historical Survey Commissions not only to designate and protect significant townscapes and rural landscapes as historical districts, but also to monitor encroachments and inappropriate construction affecting esthetic and associative values at or near historic sites. State legislation to restrict the exercise of eminent domain by utility companies for pipelines and transmission line routes in such areas is highly desirable.