James, et. al:
Given the large number of historic bridges over the Marais des Cygnes River in Kansas, it would seem appropriate for me to create a category for this river. But, this situation is a bit complicated.
1. This river is known as the Osage River in Missouri.
2. The name change does not take effect at the state line, but rather at the confluence between this river and the Little Osage River.
So, should we combine bridges over the Marais des Cygnes (both in Kansas and Missouri) with the Osage River bridges, or should we make another category called "Marais des Cygnes River for bridges over this river in both Kansas and Missouri?