BENCHMARKS continued
Slowly but surely the Liffey quays from Heuston Bridge to the Irish Sea are giving up their benchmark secrets. This one, on the river wall at Usher's Quay, lines up precisely with the centre line of Saint Paul's Church on the opposite side of the river.
Below: The 'mark on Usher's Quay.
Above: Usher's Quay looking across the wide Liffey. The 'mark is on the river wall at centre bottom.