Seeing this theme immediately gave me the idea to recreate the opening shot of London’s River Thames from the long running British TV soap opera, Eastenders:
Cessna Caravan - Martinique, vicinity of LFFF Airport Le Lamentin.
La Manzo is a lake in the hills feeding Ravine Saint-Pierre, a small stream emanating from it and regulating its water level. There is a dam, barrier La Manzo and an aquaduct. The lake itself is fed from various small mountain streams.
Although this scenery is not marked as a POI on Martinique, imho it deserves one…
Exploring the Panama Canal and flying over the Bridge of the Americas on short final into Albrook Gelabert Airport in Panama City, Panama. The Canal doesn’t technically qualify as a “river” but I figured it was in the spirit of the OP.