|This article does not cite any references or sources. (August 2014)|
|Part of the Paraguayan War|
Passagem do Chaco, oil on canvas by Pedro Américo
|Empire of Brazil|
|Commanders and leaders|
| Francisco Solano López
| Marquis of Caxias
General Juan Andrés
|12,500 men||31,000 men|
|Casualties and losses|
|15,000 dead (military and civilian)||3,000 dead|
The so-called Pikysyry maneuver was a tactic used by Brazilian marshal Luís Alves de Lima e Silva, Duke of Caxias, during the Paraguayan War. It is considered[according to whom?] the most daring and creative strategy of the entire conflict.
To circumvent it, Caxias decided to build an 11-kilometer-long road on the right bank of the Paraguay River, passing through the Gran Chaco swamps, and leading to the Paraguayan rear.
With the aid of the Brazilian Imperial Navy, Caxias carried 31,000 troops to the beginning of the road, from where they advanced along the right river bank, outflanking the enemy's fortified position.
The Navy ships, after reaching Angostura pass, sailed north, where they re-embarked the troops from the road and carried them to the left bank in San Antonio, north of the enemy position.
Due to advancement Brazilian naval, President Lopez gave up defending the line Tebicuary River, installing a more defensive front near Asunción.
After evaluating various positions, including Poí Estero, which drains the lake to the river Paraguay Ypoá, eventually organize a new defensive line, north of the creek Piquisiry, which was installed in early September 1868.15 The new position had several advantages On one hand, the attack from the south was to be made by ground troops crossed uninhabited floodplain, wooded and full of thorns. The second advantage was that at its west end, just north of the mouth of the creek Piquisiry in Paraguay, the river had a strong curve with a marked narrowing, dominated by high canyon, the "Angostura". If they could outflank the defensive position, should face the broken landscape with steep hills Piquisiry there from north, on which they could build defenses, forcing the attackers to attack forces from the narrow streambeds that cross.
The position had great against: the new battleground was no more than 35 km from the capital, Asunción, his fall, or enemy action signifying a rodeo in the same mean the fall of the capital. So Sanchez Vice President ordered the evacuation of Asuncion. The national government was installed from the February 22, 1868 in the city of Luque, who - but close - not the banks of the Paraguay River. With the advance of Brazilians, the capital would be moved again on December 8, this time to Piribebuy, much more to the east. By order of Lopez, the British engineer George Thompson raised a long line of fortifications between the Paraguay River waterfront and lagoon Ypoá. In practice, the line did not come this far east, but spread over 10 km., To the marshes that extend to the east of the lagoon. Near the eastern boundary line, the hills of Ita Cumbarity Yvate and very close to each other and separated by a brook, Lopez Lomas Valentinas christened these, and they established their headquarters. The defensive line had 85 artillery pieces of various calibers more, plus 18 guns battery deployed in Angostura, one of the guns of the latter position was the huge "Criollo", cast in casting Ybycuí, the piece largest artillery which had operated until then in South America.
Although it took two months to raise the new fortification had no major problems doing that, because the Brazilian squad "slept on the glory of catching Humaitd".
North of the Paraguayan defensive position had a significant population, Villeta, which served as a supply center and port of the army.
In early December, Lopez had 12,000 men for its defense, mostly teens and seniors
Solano López, believing that the allied troops could not cross Chaco, was caught by surprise when the allied troops assaulted his rear, being forced to retreat with his surviving troops. This led to the battles of Itororó, Avaí and Lomas Valentinas.
- http://web.archive.org/web/20091027012012/http://br.geocities.com/guerrapara/dezembrada.htm (Portuguese)
- http://web.archive.org/web/20091027111502/http://www.geocities.com/Pentagon/Camp/2523 (English)
- http://web.archive.org/web/20091027043104/http://geocities.com/ulysses_costa/Guerradoparaguai (Portuguese)