What is the Skyscrapers puzzle?
Skyscrapers is a grid-based number logic puzzle, also known as Towers. A 4x4 Skyscrapers puzzle uses the numbers 1 to 4, a 9x9 puzzle uses the numbers 1 to 9, and each number represents a building height.
The goal is to complete the grid so every row and column contains each height exactly once. The numbers outside the grid are visibility clues: they tell you how many buildings can be seen when looking from that edge.
- Use every height from 1 to the grid size in each row.
- Use every height from 1 to the grid size in each column.
- A taller tower hides any shorter towers behind it.
- Each outside clue gives the number of visible towers from that direction.
- Starter numbers cannot be changed.
How to play Skyscrapers online
Click or tap an empty square, then choose a building height from the number buttons. On a 6x6 board the available heights are 1 to 6; on a 9x9 board they are 1 to 9.
Read each clue as a view into the row or column. If the clue is 1, the tallest tower must be first because it blocks everything behind it. If the clue equals the grid size, the whole line must rise in order from shortest to tallest.
- Start with clues of 1 and N because they create direct placements.
- Use row and column rules to avoid repeated heights.
- Compare opposite clues on the same line.
- Use Check for feedback without revealing the full answer.
- Use New puzzle to keep the same size and difficulty.
Grid sizes and difficulties
This online Skyscrapers game includes 4x4, 5x5, 6x6, 7x7, 8x8 and 9x9 boards. Smaller grids are quick and friendly, while larger Towers puzzles create longer rows, more hidden buildings and deeper elimination.
Difficulty changes the number of starter cells. Easy puzzles include more given numbers, medium puzzles leave more space, and hard puzzles ask you to squeeze more information out of the skyline clues.
- 4x4 and 5x5: best for learning Skyscrapers rules.
- 6x6 and 7x7: balanced Towers puzzles for regular play.
- 8x8 and 9x9: larger skyline logic puzzles with more strategy.
- Easy: more starter numbers and clearer openings.
- Hard: fewer starter numbers and more multi-step deductions.
Skyscrapers strategy tips
Look for extremes first. A clue of 1 places the tallest building at the edge. A clue of N forces a complete rising sequence. Near-extreme clues are also powerful because they limit where the tallest buildings can hide.
Opposite clues are especially useful. If one side sees many towers and the other sees only one or two, the taller buildings are likely pushed toward the low-clue side. Combine that with missing heights in the row or column.
- Mark the tallest tower when a clue is 1.
- Fill a full ascending line when a clue equals the grid size.
- Remember that small towers are visible only before a taller tower appears.
- Use placed tall towers to block views and test clue counts.
- Treat every completed row as new information for crossing columns.
Unique Towers puzzles from 4x4 to 9x9
Every puzzle generated here is checked for a unique solution before it is shown. The board keeps the classic edge clues, then adds starter numbers according to the selected difficulty until the puzzle has one answer.
That means you can play quick beginner Towers puzzles or larger 9x9 Skyscrapers puzzles without guessing. The page stays focused on one evergreen game and guide, so players can learn the rules, practise strategy and start a fresh free puzzle in the same place.