It runs west from the high plateau between Shotts[1] and Fauldhouse to its joining with the much larger River Clyde.

[2] It is known that the ancient Romans constructed roads through Wishaw and Motherwell not too far from the river, and the ruins of the fort at Bothwellhaugh lies at the convergence of the Calder with the Clyde.

The South Calder Water follows a short course of approximately ten miles (16 kilometres), during which it winds round Shotts, Wishaw and Motherwell before flowing into the Strathclyde Loch.

[5] Between its source at Calderhead and Newmains the stream follows a wide glacial valley and passes the villages of Bonkle and Murdostoun Castle, but after Newmains, until its end at Strathclyde Loch in Motherwell, it cuts through a very deep and meandering valley.

The river is therefore placed in a "cut and cover" tunnel as it passes for approximately one-half mile (800 metres) underneath the site, before reappearing at Jerviston.