6000 BC  Objects found in archeological sites within the limits of Itaipu Lake prove the presence of humans in this region since 6000 BC.

1494  Tordesilhas agreement establishes that the entire region belongs to Spain.

1500  The Portuguese with Pedro Alvares Cabral arrived in Brazil.

1516  The Spaniards with Major Juan Dias de Solis navigate the De La Plata River. On their return trip to Spain, they are shipwrecked near Santa Catarina Island from which Aleixo Garcia reaches the Andes. Upon his return, he is killed on the bank of the Paraguay River.

1536  Foundation of Buenos Aires (Capital of Argentina) by Pedro de Mendoza.

1537  Foundation of Asuncion (Capital of Paraguay) by Juan de Salazar, near the place where Aleijo Garcia was killed.

1554  The Spaniards begin to colonize the left bank of the Parana River, they found the village of Ontiveros near the Ivai River and two years later transfer the colony to the Piquiri River, renaming it Real del Guaira Town. Afterwards, they found Vila Rica on the left bank of the Ivai River.

1609 to 1628  The Spanish Jesuits found 12 Jesuit missions on the tributaries of the left bank of the Parana River. Two are founded in the Iguassu region; Santa Maria or Concepcion (20 km upstream from the falls), and Natividade (on the right bank of the Parana River at the confluence of the Acaray River). These two sites haven´t been located yet.

1628  Members of expeditions from Sao Paulo (Bandeirantes - mamelucos) for the first time try to destroy the missions and capture Indians to sell as slaves.

1631  In one of the most extraordinary episodes in history, the missionaries and 12,000 Guaranis leave the missions in 700 canoes on the Parana river, pass through the Sete Quedas (Seven Falls) region, which, today, is submerged under the Itaipu Lake, and head toward the south, to the region of Tapes, today a territory that is divided among Brazil, Paraguay and Argentina, and found new missions.

1675  During the last expedition to Parana. Francisco Pedroso Xavier destroys Villa Rica.

1750  The Madrid Treaty establishes new borders, legitimizing Portuguese domination of the region.

1768  The Jesuits are expelled by the Spaniards and the missions of Tapes are abandoned.

1777  Due to the activities of expedition members, following the principle of  "uti possi de tis" (old latin precept of the Roman dominion), in 1750, Spain and Portugal celebrate the Madrid Treaty, ratified by the Santo Ildefonso Treaty in 1777 that with a few modifications gives the region its present configuration.

1810  Argentinean Independence.

1811  Paraguayan Independence.

1822  Brazilian Independence.

1872  Border between Brazil and Paraguay is set.

1881  Beginning of the exportation of yerba mate (Ilex Paraguayensis - mate tea tree) by Argentinean merchants.

1887  Political differences in the Missiones Province (Argentina), cause several Argentinean families to settle on the right bank of the Iguassu River (Brazil) and begin to harvest yerba mate (mate tea).

1889  The Brazilians are afraid of losing the region and send the military and engineer Belarmino de Mendonca to Foz do Iguassu (the Brazilian city) with the objective of establishing a military outpost, only 324 settlers and the natives live in Iguassu area at this time.

1890  Tourism activity starts on the Argentinean side.

1903  Three landmarks are set up, to mark the symbolic frontiers in the Iguassu region.

1910  Borders between Brazil and Argentina are set.

1914  Foz do Iguassu becomes a municipal district.

1916  Alberto Santos Dumont visits the falls and starts to work for the creation of the Park.

1918  Moises Bertoni publishes the first newspaper in Iguassu (Portuguese and Spanish).

1919  The area in which the falls are located (Brazilian side) is made public and is considered state-owned.

1920  The first road linking Foz with other cities is opened.

1930  The yerba mate (mate tea) economic cycle ends and an economy based on the timber industry begins.

1934  The Iguassu National Park (Argentinean side) is created after making the land public in 1928.

1939  The Iguassu National Park (Brazilian side) is made official by the Brazilian government with the issuance of Decree 1035 on January 10th.

1957  Foundation of Puerto Strossner (today called Ciudade del Este) on the Paraguayan border.

1965  Opening of Friendship Bridge between Brazil and Paraguay.

1969  Opening of a paved highway linking Paraguay to the Atlantic Ocean.

1975  Construction of Itaipu Hydroelectric Dam begins.

1985  Opening of the Tancredo Neves Bridge between Brazil and Argentina.

1986  UNESCO declares the Iguassu National Park a World Heritage Site.

1991  Construction of Itaipu Hydroelectric Power Plant ends.

1995  Mercosul (Common market) starts working to facilitate trade between Brazil, Paraguay, Argentina and Uruguay.

1997  Athletes from every corner of the world compete in the first World Nature Games in the Iguassu region.