11x11 Queens Puzzle #283
Difficulty: hard. Place 11 queens on this 11x11 board so that no two share a row, column or color region and none touch — including diagonally. This puzzle has exactly one solution, and it has been verified solvable by deduction alone: the complete 17-step reasoning is written out below.
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Step-by-step solution for puzzle #283
What follows is a complete solve of puzzle #283, worked the way a person works it rather than the way a computer does. It runs to 17 deductions — 11 queen placements and 6 elimination steps that narrow the board between them. Each step names the rule that forces it, so nothing below is a guess, and the hardest idea required is the pairing argument on columns.
Techniques this board needs: last square in a region, region shadow, pairing argument on columns, region confined to one line.
Show the full walkthrough (9 steps) — contains the solution
Step 1. Only row 7, column 7 is still open in pale yellow, and since each colour must take a queen, that settles it. That clears row 7, column 7, the rest of the pale yellow region and every square adjacent to it — diagonals included.
Step 2. Teal is down to 4 candidates in rows 10 and 11, columns 9–11, and they overlap enough to cover 1 square elsewhere. Cross those out without deciding anything about teal itself.
Step 3. Amber, mint, and teal are now boxed into columns 9–11 and nothing else. That is 3 colours needing 3 columns, so they fill those columns between them — which locks every remaining colour out and removes 11 squares at once.
The board after step 3 — 1 of 11 queens placed. Step 4. The sea green region is down to one open square, at row 10, column 8. Every colour holds exactly one queen, so that square is forced. Row 10 and column 8 are now spoken for, along with the squares touching that queen.
Step 5. Indigo is down to 3 candidates in rows 1 and 3, columns 5 and 6, and they overlap enough to cover 2 squares elsewhere. Cross those out without deciding anything about indigo itself.
Step 6. The slate region has 3 squares left, spread across rows 4 and 5, columns 5 and 6. You do not need to know which of them takes the queen: every one of those options attacks the same 2 squares, so they can be crossed out now.
The board after step 6 — 2 of 11 queens placed. Step 7. Indigo cannot leave row 1 — every one of its open squares (2 open squares) sits there. That row belongs to indigo, so every square on it owned by another colour is dead: 7 squares in all.
Step 8. All of the amber region's remaining squares (2 open squares) lie in column 10. Its queen therefore has to be somewhere in that column, which means no other colour may use it: 7 squares come off.
Step 9. From here the board cascades. Keep alternating the region sweep and the line sweep and 9 queens fall out in order without any new idea being needed: teal has one square left, so its queen takes row 11, column 11; mint has one square left, so its queen takes row 4, column 9; amber has one square left, so its queen takes row 2, column 10; slate has one square left, so its queen takes row 5, column 6; indigo has one square left, so its queen takes row 1, column 5; orange has one square left, so its queen takes row 9, column 4; khaki has one square left, so its queen takes row 8, column 1; blue has one square left, so its queen takes row 3, column 2; red has one square left, so its queen takes row 6, column 3. After each one, clear that row, that column, the rest of the colour and the ring of neighbours before looking for the next. The last of them seats the queen on row 6, column 3.
The board after step 9 — 11 of 11 queens placed.
That completes the board: 11 queens seated, one in every row, one in every column and one in every colour, with no two of them touching. Notice that nothing in the sequence above required a guess — each placement followed from an elimination already on the grid, which is what “single solution, solvable by logic” actually means in practice.
About 11x11 Queens puzzle #283
11x11 puzzle #283 is rated hard. Eleven colored regions cover its 121 squares, and your job is to seat eleven queens so that every row, column and color contains exactly one — with no queen touching another, including diagonally.
Like every board on this site, #283 has been verified to have exactly one valid solution, and that solution is reachable by deduction alone. You never have to guess and then unwind; every queen can be justified by something already visible on the grid. What changes from puzzle to puzzle is where the first certainty appears and how long the chain of reasoning runs before the next one — and that is entirely a product of how these particular colors are shaped.
How the colors divide this board
From smallest to largest, the regions on puzzle #283 are: pale yellow (1 square), teal (4 squares), amber (5 squares), khaki (7 squares), indigo (9 squares), mint (9 squares), sea green (11 squares), blue (15 squares), slate (17 squares), red (19 squares), orange (24 squares). An even split would hand every color 11 squares, so the pale yellow region is running 10 squares under that average while the orange region is the roomiest area on the grid with 24 squares.
That imbalance is the first thing to read, because every region takes exactly one queen regardless of how much space it owns. Pale yellow has only 1 place to put its queen; orange has 24. The spread between them on this board is 23 squares, and the wider that spread runs, the more it pays to solve from the small end inward.
A region's outline can constrain it more than its size does. Here pale yellow is the most solid, filling 100% of its 1×1 box, and sea green the most diffuse at 55% of its 5×4 box. Solid blocks give clean eliminations; diffuse ones spread across the board and stay open longer.
Region by region
The complete breakdown of each region on this board follows, ordered from tightest to roomiest. Skimming the spans first tells you where the board is crowded and where it has slack.
Pale yellow covers 1 square, spanning 1 row and 1 column (rows 7–7, columns 7–7). It never leaves row 7, so its queen is locked to that row.
Teal occupies 4 squares within rows 10–11, columns 9–11.
Amber: 5 squares across rows 1–3, columns 9–11.
Khaki covers 7 squares, spanning 4 rows and 2 columns (rows 8–11, columns 1–2).
Indigo occupies 9 squares within rows 1–3, columns 5–8.
Mint: 9 squares across rows 2–5, columns 9–11.
Sea green covers 11 squares, spanning 5 rows and 4 columns (rows 6–10, columns 8–11).
Blue occupies 15 squares within rows 1–4, columns 1–6.
Slate: 17 squares across rows 4–8, columns 5–10.
Red covers 19 squares, spanning 7 rows and 4 columns (rows 3–9, columns 1–4).
Orange occupies 24 squares within rows 5–11, columns 3–8.
Where to start on this board
The most constrained color is where a solve should begin, and on #283 that is pale yellow with 1 square. It reaches from row 7 to row 7 and from column 7 to column 7 — 1 row by 1 column. One queen has to live inside that footprint no matter what else happens, which makes those lines the busiest real estate on the board.
Because pale yellow never leaves row 7, its queen must be in that row — and that instantly settles row 7 for everyone else. Sweep along it and X out every square that is not pale yellow. Then look at which colors just lost ground: on a grid this size that one observation usually forces a second region within a move or two.
Work outward to the other flat regions next. Teal is no more than two rows tall, so its queen is confined to a narrow band. When two flat regions overlap the same pair of rows, those rows are spoken for and every other color is locked out of both — the single most productive pattern in the game, and it is live on this board.
The tightest lines on puzzle #283
A quick way to find the next move is to count how many different colors touch each line. On this board, rows 1 and 11 are the narrowest, touched by only 3 colors. Columns 1, 2, 3 and 4 are the tightest columns, with 3 colors.
The fewer colors a line touches, the sooner it surrenders its queen. A row meeting just 3 colors has to be claimed by one of them, which pushes every remaining region into the other 10 rows. Row 8, meeting 5 colors, is the opposite case — the busiest line on #283 and the last one you should expect to crack.
Working through the middle game
Past the opening, treat this as an elimination exercise rather than a placement exercise. Each queen takes out a row, a column and its eight neighbours, and the value of a move is measured by how much it removes. Cross everything out as you go and let the board do the remembering.
Keep alternating between two views of the board. In the region view you ask which of the eleven colors is down to one open square. In the line view you ask the same of each row and column. Both produce forced queens, and each placement refreshes the other view, so cycling between them deliberately is how a 11x11 board unwinds.
Say the reason out loud: "this region has one square left", "this column has one square left". If no such sentence is available, the eliminating is not finished. One more pass of X marks is almost always quicker than committing to a placement you cannot defend.
Why puzzle #283 is rated hard
Ratings track how generous the opening is. On #283 you get two regions pinned to a single row or column, a smallest color of 1 square, a tightest row crossed by 3 colors, and a 23-square gap between the largest and smallest regions. Those four numbers largely explain the hard label.
The scale has nothing to do with maths or luck — every puzzle here is solvable by deduction and has exactly one answer. It measures reasoning depth: how many eliminations must stack up before a placement becomes provable. That depth is what separates a hard board from the rest.
If #283 feels harder than its rating suggests, the usual culprit is incomplete marking rather than a difficult deduction. Check that every queen already on the grid has its full cross of eliminations recorded — including the diagonal neighbours, which are by far the easiest to miss. More stalled solves come from one forgotten diagonal X than from any genuinely deep chain of logic.
Techniques that work well at 11x11
At 11x11 you are managing 121 squares, and holding the whole board in your head will not work. Split it into quadrants and solve locally. Most useful deductions on a grid this large are regional — a color pinched between two placed queens, or a band of rows that two regions must share. Trust the marks on the board over your memory.
One pattern is worth learning at every size, and it is available here. When two regions can only fit inside the same two rows, they must take one row each — which locks every other region out of both. The same argument works for columns, and for any matching count: three regions sharing three rows, four sharing four. Spotting these pairings turns a slow grind into a quick cascade, and on #283 the place to look for one is around row 1.
Here is a shape check that gives nothing away: when #283 is solved, 3 queens sit on the outer edge of the grid and 8 sit inside it, with 1 queen in a corner. A work-in-progress board that clusters its queens in one quadrant while leaving others bare is usually carrying a mistake.
How to play Queens
- The board is an N×N grid divided into N colored regions.
- Place exactly one queen (♛) in each row, each column, and each colored region.
- No two queens may touch each other — not horizontally, vertically, or diagonally.
- Tap once to mark a square with an X (where a queen can't go), tap again to place a queen, and once more to clear it.
- There is always exactly one valid solution. Use logic, never guessing, to find it.
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Questions about this puzzle
How hard is 11x11 Queens puzzle #283?
Puzzle #283 is rated hard. Its smallest color region holds 1 square, its tightest row is touched by 3 colors, and two of its regions are confined to a single row or column, which gives you a forced move early.
Does 11x11 puzzle #283 have only one solution?
Yes. Every puzzle in the 11x11 collection, including #283, has been verified to have exactly one valid arrangement of eleven queens, and it can always be reached by logic alone — no guessing or backtracking needed.
Where should I place my first queen on puzzle #283?
Start with the pale yellow region — the most constrained color on this board, with 1 square spanning rows 7–7 and columns 7–7. Narrowing the smallest region first removes the most squares elsewhere on the grid.