Bourke Base Line Historic Marker - NSW

This Survey Beacon, built in 1915 is the Northern end of an accurately measured Trigonometrical Base Line, 30 km long, which was part of Australians first National Mapping Scheme.

The Southern end of the base is towards Byrock and just off the Highway. The Base Line was laid out in 1911. This Beacon was intervisible with South Base and Moira Trigonometrical Station on Mt Oxley.

The whole process of measurement and check measurement between bases took surveyors more than two months, including 3 weeks to clear the line, defining the alignment and placing pegs every 24 metres.