Battle of Ybybobó
1934 CE.
Shown on the map at -21.542°, -62.994°.
The Battle of Ybibobó was fought in late December 1934 by Bolvia and Paraguay during the Chaco War. The Bolivian 9th Division, on a recently established defensive line around Ybybobó, was encircled and made to surrender. The Paraguayan victory allowed them access to the foothills of the Andes, expelling Bolivia from one of its last positions in the Chaco.
Text from the Wikipedia article Battle of Ybibobó, licensed CC BY-SA 4.0.