Illinois State Route 99 runs briefly in Northeastern Pike County. This is the southern most county it passes through. IL St Rt 99 does not pass through any towns in Pike County. IL St Rt 99 is not multi-plexed in Pike County. IL St Rt 99 intersects the following highway in Pike County. Illinois State Route 104, near Meredosia.
SB IL St Rt 99 at the Brown/Pike County. A junction marker on EB IL St Rt 104. A junction marker on WB IL St Rt 104. A guide marker on WB IL St Rt 104. The southern end near Meredosia. The southern end marker.
