OBB Austria Rail 52 puzzle, based on an original photo by Antonio Martinetti (photo copyright Antonio Martinetti -- used with permission). Photographed at Naglern, Austria, October 4, 2021.
Click here for more information about this photograph
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.