Kimberly is one of three movies that Sean Astin and His Mom Patty Duke appear in the same film. The other two are Bigger Than The Sky and Amazing Love.
Filmed at Schukyll River's famous & picturesque Boathouse Row just upriver from the Philadelphia Museum of Art and the historic Water Works. Museum is the beautiful gold-coloured Greek Revival building with columns above curve of river, first seen during first or second rowing sequence. Rowing is done only above the falls at the Water Works, where Schukyll River drops into upper tidal stretch before Delaware River.
Scene in which Walter and Nancy fight and she walks away appears to have been shot in 18th-C Elfreth's Alley in (old) Center City Philadelphia. One of oldest original continuously-inhabited streets in the US.