Bolivia–Peru border
From the Altiplano across Lake Titicaca, the world’s highest lake navigable by large ships, north into the Amazon. Its unexplored northern half was settled by Argentina’s president as arbitrator in 1909.
Written from cited sourcesLast checked 29 September 2026Suggest a correction
See it on the globe:Bolivia →Peru →
Titicaca
Lake Titicaca lies astride the border, with Peru to the west and Bolivia to the east. At 3,810 metres it is the highest lake in the world navigable by large vessels, and it covers about 8,300 km², stretching 190 km from northwest to southeast. The narrow Tiquina strait divides it into a larger northwestern and a smaller southeastern basin.[1]
Ruins on its shores and islands, including Tiwanaku in Bolivia, attest to one of the oldest civilisations in the Americas, and the Incas placed the origin of their dynasty on Titicaca Island.[1] In 1996 the two countries created a binational authority, the ALT, by treaty to manage and develop the Titicaca basin.[3]
Arbitration by Argentina
A treaty of 23 September 1902 settled the southern part of the border, from Tacna and Arica to the River Suches. For the rest, running north into the Amazon basin, the two countries agreed on 30 December 1902 to let the Argentine government decide. Everything that in 1810 belonged to the Audiencia of Charcas would go to Bolivia, and what belonged to the Viceroyalty of Lima to Peru.[2]
Bolivia claimed a line far to the north and west, down the Urubamba; Peru claimed a line far to the south and east, along the Madidi and Beni. President José Figueroa Alcorta found that neither side’s colonial titles settled the question, since the disputed zone had been unexplored in 1810 and long after. On 9 July 1909 he fixed the line on grounds of equity, and the two countries accepted it by a protocol of 15 September 1909.[2]
Timeline
190121 November 1901
Arbitration treaty
Bolivia and Peru agree to arbitrate their disputes.[2]
190223 September 1902
Southern sector
The line from Tacna and Arica to the Suches is settled.[2]
190230 December 1902
Case to Argentina
The rest of the border is submitted to the Argentine government.[2]
19099 July 1909
Award
Argentina’s president draws the northern line.[2]
1996
Lake authority
A binational authority for the Titicaca basin is created.[3]
More borders
Sources
- [1]Lake Titicaca · Encyclopaedia Britannica (Wayback Machine copy)
- [2]The Boundary Case between Bolivia and Peru (compromis of 30 December 1902, award of 9 July 1909), RIAA vol. XI, pp. 133–146 · United Nations, Reports of International Arbitral Awards · 9 July 1909
- [3]
Map geometry from Natural Earth via world-atlas. See credits.