by Marcos Maté
Continental Rail 335 puzzle, based on an original photo by Marcos Maté (photo copyright Marcos Maté -- used with permission). Photographed at Pancorbo (Burgos), Spain, November 20, 2019.
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.