Legislative Route 1/Sycamore Allee is an historic roadway landscape illustrating prevailing styles of early 20th century landscape architecture located in Halifax and Reed Townships. The northern part of the route corresponds to the Shamokin Pass, a road that appeared on area maps as early as 1759. At the time, it was the only route between Harrisburg and Sunbury. The south end of the route, a road around the western side of Peters Mountain, appeared on maps by 1770. In 1911 the combined route was designated Legislative Route 1 by the Sproul Highway Act, the act which established the state highway system. In 1920 and 1921, the route was paved. During this period, the Department of Highways in conjunction with the Department of Forests & Water instituted a tree planting program along important Pennsylvania roads. As part of this project, 536 sycamore trees were planted along Legislative Route 1 in 1922. Now known as Route 147, 314 of the original sycamore trees remain along the route. They line both sides of the road south of Halifax and line the east side of the road north.