Mount Cottrell massacre
1836 CE.
Shown on the map at -37.769°, 144.634°.
The Mount Cottrell massacre involved the murder of an estimated 10 Wathaurung people near Mount Cottrell in the colony of Victoria in 1836, in retaliation for the killing of two European settlers, one of whom had been poisoning Indigenous Australians.
Text from the Wikipedia article Mount Cottrell massacre, licensed CC BY-SA 4.0.