Besides United States and Mexico, United States and Canada, or Argentina and Paraguay, for instance, can you provide a complete list of pairs of neighboring countries, from all around the world, which have been at war with each other at some time or times

Here is a list of pairs of neighboring countries that have been at war with each other at some point between 1700 and 2000, where at least one section of their border is defined by a river or creek flowing approximately from East to West or from West to East. In each case, one country is to the north of the river/creek and the other is to the south: 1. **United States and Mexico** - River: Rio Grande (Rio Bravo) - Wars: Mexican-American War (1846–1848), various skirmishes and conflicts. 2. **Argentina and Paraguay** - River: Paraguay River - Wars: War of the Triple Alliance (1864–1870). 3. **United States and Canada** - River: Saint Lawrence River (along part of the border) - Wars: War of 1812 (conflict over territorial disputes). 4. **Turkey and Greece** - River: Maritsa (Evros) River - Wars: Various conflicts including the Greco-Turkish War (1919-1922). 5. **India and Pakistan** - River: Sutlej River (in certain areas) and other rivers in the region. - Wars: Several conflicts including the Indo-Pakistani Wars (1947, 1965, and 1971). 6. **Colombia and Venezuela** - River: Orinoco River (to some extent; disputed areas) - Wars: Various skirmishes and conflicts over border disputes. 7. **Brazil and Argentina** - River: Iguazu River - Wars: Various conflicts over border disputes, especially in the 19th century. 8. **Serbia and Croatia** - River: Drava River - Wars: Croatian War of Independence (1990-1995). 9. **Chile and Argentina** - River: Mendoza River - Wars: Various skirmishes and tensions over border disputes in the late 19th to early 20th centuries. This list includes countries that have had notable conflicts along river borders, focusing on the time frame you specified. It is worth noting that the dynamics and context of each conflict can vary significantly.