--- title: "Free Bridges generator with answers | Once Books" description: "A free Bridges (Hashiwokakero) generator that makes a printable puzzle and its answer in one click. Every puzzle joins up exactly one way, with no sign-up and no watermark." source: "https://www.oncebooks.com/tools/bridges-generator" --- 1. [Home](https://www.oncebooks.com/) 2. [Tools](https://www.oncebooks.com/tools) 3. Bridges generator Free tool # Free Bridges generator, with the answer Pick a board and generate a Bridges puzzle, then print it with its finished network. Every puzzle joins up exactly one way, with no sign-up and no watermark. It runs on the same engine as our KDP Publisher Studio. PuzzleDesign Difficulty More islands is what makes a board harder, not a bigger grid. A wide board with few islands gives the numbers almost nothing to choose between, so the grades add islands and grow the board to fit them. 11×11 board, 18 islands. Join the islands with bridges along the rows and columns so each holds exactly its number of bridge ends, no two bridges cross, at most two join any pair, and every island ends up in one connected network. Theme ClassicBoldSoftShadedNavyIndigoSkyTealEmeraldForestPlumBerryCrimsonEmberAmberCocoa **Customise colours** Numbers Cell lines Box lines Page background Style StandardClean Clean drops the title band and footer, leaving the grid. Generate puzzlePrint / save PDF Two pages: the puzzle and its answer. Every puzzle is proved to have exactly one answer by the same engine as our KDP studio. ## Want the whole book? This makes one puzzle. Sign up to turn it into a full Bridges book for Amazon KDP: hundreds of graded puzzles at any trim, as print-ready PDFs. [Build the full book](https://app.oncebooks.com/publisher-studio/bridges/edit?from=bridges&v=2&s=eyJkaWZmaWN1bHR5IjoiSEFSRCIsImNvbG9yVGhlbWUiOnsidGhlbWVJZCI6ImNsYXNzaWMiLCJvdmVycmlkZXMiOnt9fX0) Free to build · pay once to export Preview The puzzle and its answer, as they print. Hide the preview - Bridges Hard 1 Puzzle - Bridges Hard · Solution 2 Solution Generate puzzlePrint / save PDF ## How to make a Bridges puzzle 1. Pick a difficulty. Choose a board. Harder grades put more islands on a bigger grid. 2. Generate the puzzle. Press Generate puzzle. You get a fresh board, proved to join up exactly one way. 3. Print the two pages. Press Print / save PDF. You get two pages: the puzzle on page one and its finished network on page two. ## How to solve a bridges puzzle Join the numbered islands with bridges running along the rows and columns, so that each island holds exactly its number of bridge ends, no two bridges cross, at most two join any pair, and every island ends up in one connected network. ### The method 1. Start with the islands that have no choice. Count an island’s neighbours and work out the most bridges it could possibly take: two to each. An island marked 4 with only two neighbours must send two each way. A 6 with three neighbours is the same. Those are free, and they usually open a corner. 2. Use the almost-full islands next. An island marked 3 with two neighbours must send at least one bridge each way, because two to one side would leave three for the other and three is not allowed. The same reasoning gives a 5 with three neighbours one bridge in every direction. You are not placing the whole number, just the part of it that cannot go anywhere else. 3. Watch what each bridge rules out. Every bridge you draw blocks the line it crosses, so a bridge between two islands can make a crossing bridge impossible and force its island to look elsewhere. That is usually where the next deduction comes from rather than from the numbers themselves. 4. Never close off a group. If a handful of islands have all their numbers satisfied and no bridge joins them to the rest, the whole arrangement is wrong, because every island has to end up in one network. Checking for that as you go saves you from a board that looks finished and is not. **The one rule people get wrong** Bridges never cross, and they never pass over an island either. A line from one island to another two places away is only legal if nothing at all sits between them. **What the answer page shows** The same islands with every bridge drawn in, single or double, so you can check a pair at a glance. **How the grades differ** More islands, on a bigger board to fit them. The island count is what makes a board hard: a wide board with few islands gives the numbers almost nothing to choose between. **Is it the same as a nonogram?** No, though both work from numbers at the edge of a shape. A nonogram has you shade squares from run lengths; here you draw lines between places, and the rule that no two cross is what gives the puzzle its character. **Good for** Anyone who likes a puzzle that is drawn rather than filled in. ## Publishing a whole book? This tool makes one puzzle for home or the classroom. To make a Bridges book you can sell on Amazon KDP, Publisher Studio generates hundreds of graded puzzles across a difficulty curve, at any KDP trim, as a print-ready interior and solutions PDF. [See the KDP Bridges maker](https://www.oncebooks.com/kdp-bridges-maker) ## Questions **What is a Bridges puzzle?** It is a logic puzzle, also called Hashiwokakero, played on a board of numbered islands. You join the islands with bridges that run straight along the rows and columns. Each island must end up holding exactly its number of bridge ends, no two bridges may cross, at most two bridges may join the same pair, and every island has to end up in one single connected network. **Is this Bridges generator free?** Yes. Pick a grade, generate a puzzle and print it with its answer, with no sign-up and no watermark. It is free for classroom, home and personal use. **How do I start solving one?** Start with the islands whose number is as big as it can possibly be. An island marked 4 with only two neighbours must send two bridges to each of them. The same argument works on a 3 with two neighbours: at least one bridge has to go each way, because two to one side would leave three to the other. Those forced bridges then give their neighbours the same kind of certainty. **Why can my network not be two separate groups?** Because the rule says every island joins one network, and it is the rule that does most of the work at the end of a puzzle. If a group of islands has all of its numbers satisfied and is not touching the rest, it can never gain another bridge, so that arrangement is wrong however neat it looks. Spotting one of those early saves a lot of rubbing out. **Is it the same as a maze or a number puzzle?** Neither, really. There is nothing to add up: the numbers count bridge ends rather than feeding an arithmetic, and nothing is traced through a passage. It is closest to the puzzles where you work out a shape from counts, so it suits people who like nonograms but would rather draw lines than shade squares. **Does every puzzle have one solution?** Yes, and here it takes real work to guarantee. Adding bridges to a board usually gives the numbers somewhere else to be satisfied, so every bridge beyond the first network is tried against a solver and kept only while the board still joins up one way. **What size are the pages?** The free tool prints at 8.25 by 11 inches, a popular large-print size. Our Publisher Studio will export the same book at any KDP trim, from 5.06 by 7.81 up to 8.27 by 11.69, as a print-ready 300 DPI interior. Short of ideas? Browse our [ready-made printables for this puzzle](https://www.oncebooks.com/bridges) and print one today.