by Robert King
Buffalo & Pittsburgh SD40-3 puzzle, based on an original photo by Robert King (photo copyright Robert King -- used with permission). Photographed at Brockway, Pennsylvania, January 26, 2018.
The "Easy" version of the puzzle has about 100 pieces, "Medium" has about 200 pieces, "Hard" is about 300 pieces. For the Online puzzles, see the Online Puzzle Tips.