Alberta Provincial Highway No. 42, commonly referred to as Highway 42, is a 44-kilometre (27 mi) highway in central Alberta, Canada that connects Highway 2A in Penhold, about 9 kilometres (6 mi) south of the city of Red Deer, to Highway 21 near the Hamlet of Lousana.

Major intersections

From west to east.

Rural/specialized municipalityLocationkmmiDestinationsNotes
Penhold0.00.0Highway 592 west Highway 2ARed Deer, InnisfailAccess to Red Deer Regional Airport; Highway 42 western terminus; continues as Highway 592
Red Deer County4.02.5Highway 2Edmonton, Red Deer, CalgaryInterchange; Highway 2 exit 384
25.916.1Highway 816 northWest end of Highway 816 concurrency
Pine Lake27.617.1Highway 816 southEast end of Highway 816 concurrency
44.027.3Highway 21Bashaw, Three Hills UAR 90 east – LousanaHighway 42 eastern terminus; continues as Urban Approach Road 90
1.000 mi = 1.609 km; 1.000 km = 0.621 mi Concurrency terminus