How to solve Skyscrapers — rules, examples and lesson

Basics

The board is a square grid of identical cells. Each cell holds a skyscraper: the larger the number, the taller the building.

The number in a cell is the building height, from 1 to the board size.
The numbers around the edge show how many buildings are visible from that side of the row or column.
Every row and every column contains each height exactly once.

Tap an edge number to see how many buildings are visible from that side.

How to place a number correctly

Correct

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3 is the only missing height: the row already has 1, 2 and 4. The left clue of 4 confirms the order 1-2-3-4.

Correct

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Only 1 building is visible from the left — so the nearest one must be the tallest (4): it hides all the others.

Wrong

4321413222121222

Not allowed: 2 is already in this row — heights must not repeat.

Guessing

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The left clue is 2 and the first cell is 3, so 4 fits in any of these cells. Guessing now is premature — other clues will pin its place.

Worked example

On the left is the starting board with only the clues; on the right is the finished solution. Below you can watch how it is built step by step.

Starting board

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Solution

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Interactive lesson

Step 1 of 125 min

Technique · visibility

What height means

The larger the number, the taller the building. A tall building hides the shorter ones behind it. Look at the row from both sides and answer the question.

Visible: 1

How many buildings are visible from the right?

4321413222121222