Amazon.com: Castorland Majesty of The Mountains Puzzle (4000 Piece) : Toys & Games
Amazon.com: CASTORLAND 4000 Piece Jigsaw Puzzles, Good Evening New York, Puzzle of NYC, Puzzles of The USA, City Skyline Puzzle, New York Harbor and Bridge Puzzle, Castorland C-400256-2 : Toys & Games
Pride of London by Castorland (4000 pieces). Really tough but enjoyable one to do! Took 48 hours 5 minutes! Have a time-lapse of it coming once I've edited it! : r/Jigsawpuzzles