What Is Castling in Chess? Simply put, castling is a special rule that allows your king to move two spaces to its right or left, while the rook on that side moves to the opposite side of the king.
Castling is one of those special rules where to be a strong player you don’t just need to know how to castle in chess, you need to master how to castle in chess!
Thankfully, castling is not too hard to get to grips with but once you know the basic rules there are a few pointers you need to be aware of.
In this quick guide, we’ll tell you everything you need to know about castling, answer all the questions that often crop up and give you some exciting examples of games where castling made the difference. And there’s even a quick puzzle to solve
What is castling in chess?
Castling is one of those special moves in chess that you need to know to play properly. It is the only time you get to move two pieces at the same time and each player is only allowed to castle once, under certain conditions.
The move is crucial, but it is also simple to learn. There are two types:
King-side castling – where the White king goes two spaces to his right, and on the other side of the board the Black king can go two spaces to his left. See this diagram with the kings moving along the red line and the rooks along the green line:
Queen-side castling – similar in that the king moves two spaces but this time the White king goes left and the Black king goes right. See here:
In both cases, the rook jumps over the king and settles next to him. One thing to remember is that if you want to castle you need to pick up the king first – not the rook. This is very important!
The final positions should look like this if White castled queen-side and Black castled king-side:
But in short, if someone asks you how to castle in chess just say it is when the king moves two spaces to his left or to his right and the rook jumps over him and ends up on the other side.
However, as always there are a number of conditions that must be met to make it a legal move or it won’t be allowed and your opponent will say “hang on a minute!” But we will get onto the nitty-gritty a bit later on and answer a few questions first.
Why castle in chess?
Castling is primarily all about getting your king safe because, usually, the move takes your most important piece out of the center of the board and tucks him away behind a wall of pawns.
Games are won and lost by players deciding if and when a player to castle. In fact, when it comes to beginners a very high proportion of games are lost simply because a novice player doesn’t get their king protected. So it pays to castle.
But beware, the timing is crucial – sometimes castling may actually put your king in danger. So, as with everything in chess, be careful.
It is for this reason that while beginners are often taught to castle as soon as they can, you often see experts put off castling until much further into the games.
Let me repeat the point: timing is crucial.
What does castling achieve in chess?
Castling does two things: 1. it creates a safe haven for your king (or should, if you do play it at the right time) and, 2. it develops your rook, bringing it out nearer to the center of the board where it can get into the game.
Castling, therefore, is a very nifty maneuver. But like every move in chess, you have to judge when the right time to play it is.
Here’s a good example of a classic game where castling at the right time was crucial. Scroll through it and see how powerful White’s castling proved:
A quick puzzle – what happens if Black castles here?
This puzzle is taken from GM Susan Polgar’s Learn Chess The Right Way series for beginners.
It is Black to move:
In order to be allowed to castle, neither the king nor the rook (on a8) could have moved at any time earlier in the game.
This rarely happens in a regular game as it is generally advisable to castle in the early part of the game. Black checkmates by castling queenside (king to c8 and rook jumps over it to d8).
Here is another example of a real-life game played in London, 1912, in which checkmate by castling could have occurred, but the winner decided to play Kd2 instead:
How to castle in chess – the rules
Remember what we said before about the king moving two spaces to the left or right and the rook jumping over? That is how you make the move on a basic level, but we also said there are a number of rules that apply to make it legal.
Castling can only happen if all of the following conditions are met in a game:
The king has not previously moved;
Your chosen rook has not previously moved;
There must be no pieces between the king and the chosen rook;
The king is not currently in check;
Your king must not pass through a square that is under attack by enemy pieces;