Battle of Campo Grande
1933 CE.
Shown on the map at -23.033°, -60.167°.
The Battle of Campo Grande was a major engagement during the Chaco War, in the southern region of the Chaco Boreal. During this battle, the Paraguayan Army successfully encircled two Bolivian regiments defending two of the three flanks of Fort Alihuatá, forcing them to surrender.
Text from the Wikipedia article Battle of Campo Grande, licensed CC BY-SA 4.0.