[2] The Camac flows from a source on Mount Seskin/Knockannavea mountain north-east of the village of Brittas (southwest of Dublin city), joining other mountain streams, before being diverted by an 18th-century diversion from the Brittas River tributary of the River Liffey.

[1][3] It flows through a mountain valley named the Slade of Saggart which lies just west of the N81 road (and below the site of the Crooksling tuberculosis sanatorium) southwest of the broad Tallaght plain and east of Newcastle.

The Slade of Saggart is a large rock-cut valley which was possibly created by fluvioglacial streams deriving from the wasting Slievethoul icecap, as noted by Hoare (1976).

It runs between Grattan Crescent Park and nearby Richmond Park (home to St Patrick's Athletic) where it gives its name to the ground's 'Camac Terrace', and arrives in Kilmainham, where it runs behind the jail museum[5] and is crossed by Bow Bridge at Bow Lane West.

The Camac receives tributaries in the Slade of Saggart, including the Ferny Glinn and the Two Slades, and later from around Newcastle, and near Clondalkin (including the Boherboy, Brownsbarn and Fettercairn Streams, the latter joining near the boundary of Corkagh Park, in which the Camac features).