The A81 crosses the River Endrick on Killearn Bridge, rather confusingly sited a couple of miles from the village of Killearn! The bridge is a simple twin arch stone bridge with the central pier sitting in the river. It carries a pavementless S2 roadway across the river. The bridge has modest decoration on the sides, with pronounced arch rings and neater bands of stone for the parapet above the rubble work below.
The only other feature of any note is that the two abutments seem to be very slightly flared compared with the two arches. The stonework all matches up at parapet level, but at the bottom of the structure, the abutments protrude a few inches wider than the bases of the arch. This is done with decorative quoins, so the structural benefit of such a design must be minimal.
