Beginning at the intersection of the center lines of Greencastle Road and the boundary line between Prince George's and Montgomery Counties, thence easterly with the center line of Greencastle Road to the center line of Old Gunpowder Road, thence northerly with the center line of Old Gunpowder Road to the center line of Van Dusen Road, thence easterly with the center line of Van Dusen Road to the center line of Virginia Manor Road, thence southeasterly and southwesterly with the center line of Virginia Manor Road to the center line of Cinder Road, thence southeasterly with the center line of Cinder Road to the center line of Baltimore Avenue (US Rt. 1), thence southwesterly with the center line of Baltimore Avenue to the center line of Muirkirk Road, thence easterly with the center line of Muirkirk Road to the center line of Odell Road, thence southwesterly with the center line of Odell Road to the center line of Springfield Road, thence easterly and southeasterly with the center line of Springfield Road to the center line of Powder Mill Road, thence easterly and northerly with the center line of Powder Mill Road to the center line of Laurel-Bowie Road (Md. 197), thence southeasterly with the center line of Laurel-Bowie Road to the center line of Telegraph Road, thence northeasterly with the center line of Telegraph Road to the center line of the Patuxent River, thence northerly and westerly with the center line of the Patuxent River to the boundary line between Prince George's and Montgomery Counties, thence following said boundary line to the point of beginning.