 I-81 enters the state near Ridgeway and travels northeast, bypassing the city of Martinsburg, and leaves the state at the Potomac River, which serves as the state line.The first solicitations for the construction of I-81 were published in 1959, with the first of freeway being opened in 1963, and the full length was completed by 1966.On average between 45 and use the freeway through the panhandle per day.