Which border rivers are there between USA and Canada?

A number of rivers make up pieces of the long US - Canada border:

1. Detroit River
2. Halls Stream: New Hampshire - Quebec
3. Monument Creek
4. Niagara River
5. Pigeon River: Minnesota - Ontario
6. Rainy River: Minnesota - Ontario
7. St. Clair River: Michigan - Ontario
8. St. Croix River: Maine - New Brunswick
9. St. Francis River Maine - Quebec
10. St. John River: Maine - New Brunswick
11. St. Lawrence River
12. St. Marys River

https://en.wikipedia.org/wiki/List_of_international_border_rivers#US.2FCanada

Rainy River forms part of the boundary between Ontario and Minnesota.
https://en.wikipedia.org/wiki/Rainy_River_%28Minnesota-Ontario%29

The border between Ontario and the USA includes the Pigeon River, St Mary's River, the St. Clair River, the Detroit River and the Niagara River, as well as Rainy River.

https://en.wikipedia.org/wiki/Definitions_of_Canadian_borders

The Saint Croix River forms a border between Maine and New Brunswick.

https://en.wikipedia.org/wiki/St._Croix_River_%28Maine_%E2%80%93_New_Brunswick%29

The St. John River also forms part of the Maine-New Brunswick border.
https://en.wikipedia.org/wiki/St._John_River_%28New_Brunswick%29