PA 35 begins at an intersection with US 522 near the borough of Shade Gap in Dublin Township, Huntingdon County, heading northeast on a two-lane undivided road.

[2][3] PA 35 enters Lack Township in Juniata County and becomes an unnamed road, passing through more valley farmland with some homes.

The route curves northeast again and continues through more wooded areas with occasional farm fields, heading into Beale Township.

[2][4] After crossing the river, the route continues east and comes to a roundabout with William Penn Highway, where it turns north onto South Main Street and runs through residential areas.

PA 35 enters the borough of Mifflintown and continues north to the commercial downtown, where it turns east onto Bridge Street.

PA 35 turns northeast and crosses into Fayette Township, passing through Oakland Mills and runs through more agricultural areas with some patches of woods and homes.

The route runs through the residential community of Mount Pleasant Mills, turning northeast and reaching an intersection with PA 104.

PA 35 heads back into Washington Township as an unnamed road and runs through more open farm fields with a few patches of woods and residences.

PA 35 continues east and crosses Penns Creek, ending at a trumpet interchange with the US 11/US 15 freeway south of the borough of Selinsgrove.