Fortín Boquerón

The Chaco War was fought between Bolivia and Paraguay from 1932 to 1935 over the northern Gran Chaco, a sparsely populated region thought to hold petroleum. Wikipedia says both countries were landlocked, and that control of the Paraguay River would give either access to the Atlantic. Historians debate how far oil companies influenced the war. Bolivian troops occupied Boqueron and other outposts in July 1932, an escalation that turned a border dispute into a full war.

The Battle of Boqueron ran from 9 to 29 September 1932. Wikipedia says about 448 Bolivians were besieged in the outpost under Colonel Manuel Marzana, while Paraguayan forces under Lieutenant Colonel Jose Felix Estigarribia attacked with a much larger force. Paraguay used mortars, which Wikipedia credits with giving a decisive advantage. Water was a serious problem for both sides, as the wells inside the compound came under fire and were contaminated. Bolivian aircraft tried to drop supplies with little success, and a relief column was driven back near Yucra.

On 26 September Estigarribia ordered an all-or-nothing attack. Three days later the remaining Bolivian defenders, about 240, mostly wounded, surrendered. Casualty figures given by Wikipedia for Bolivia do not fully reconcile, so they are best treated as approximate.

The battle opened Paraguay's offensive and is regarded as a Paraguayan victory. Wikipedia describes the Chaco War as the bloodiest war in twentieth-century South America relative to population, and says Paraguay held most of the disputed area at the ceasefire. A peace conference in Buenos Aires in 1938 gave Paraguay about three-quarters of the Gran Chaco.

Travel sources describe the site as including a museum with weapons and photographs, a cemetery of fallen soldiers, a large monument built around the original trenches and a hollowed-out tree once used as a sniper's nest. A scholarly article says the site was partially restored and turned into a visitor attraction over about two decades and is now also used for conflict archaeology. The battle is commemorated each year on 29 September.

The Chaco is remote, so the journey to Boqueron is long and the climate is hot and dry for much of the year. Travel sources place the site along the Trans-Chaco route, some distance from the Mennonite colonies of the central Chaco. A private vehicle and driver suits the distance, and a guide can bring the battle to life with maps and context. Because the site commemorates a war with large loss of life, a respectful approach is appropriate.