The route begins at Exit 461 on SH 1 near Drury and travels in a general south-west direction along Karaka Road, and then south to Pukekohe.

The highway officially terminates where SH 22 meets the northern intersection with Adams Drive.

[3] In 1944 what was to become State Highway 22 was expected to become an arterial road linking Auckland and New Plymouth.

[4] That was long before the National Roads Board, gazetted it as State Highway 22 in July 1963,[5] which designation was first shown on a one-inch map in 1971.

[6] A start was made on upgrading the road to the SH 23 junction near Te Uku in the early 1960s.