What square on a chessboard is the least visited square?

On a 64-square chessboard, which square is least visited? It's not a quiz or anything, even I don't know the answer.

a4 a5 unless its a ruy lopez.

odd little question.  I suppose someone could plug in a few thousand GM games and see.

Or a Sicilian, or Slav, or in different variations of about a dozen other openings.

The most common are probably f3,f6,c3,c6 and the 4 center squares.  After that it's hard to talk about their use.  I played online chess on my brother I-phone for 3-4 hours and when I turned the phone off I could see 64 neatly arranged finger smudges on the center of the phone (hehe) all squares are used during a game, It'd be hard to point out a least used square.

What about f4?

Poison pawn, grand prix, closed sicilian, kings gambit, and stonewalls come to mind.

I mean... maybe f4 is it, but every time I think of a square I can think of many positions it's used in, very hard for me to just name one.

Nobody plays the KG or the Grand Prix, and the Stonewall is more popular from black's side.

Bc4 for white is a more common move than Bf4, and c4 is a more common destination for a pawn than f4. You have to eliminate the four center square right from the outset, and I think black plays f4 more often than white plays f4 (KID, Dutch, Stonewall). b4 and b5 have bishop problems, along with g4 and g5. You know, h4 might be a good one, maybe better than f4. Other than the c1 bishop coming there after Bg5, h6, who ever goes to h4? And I have the impression, though it's just that, that h4 is less occupied than h5.

How do you define visited? Is a1 or a8 the least visited square?

I'd say a5 is the "emo" square!

Add to that, closed French defense with f4 pawn push

I thought corner squares would be out because they are good for trapping kings, no?  And knights always get stuck there after a fork...I'm blathering...carry on.

OK OK I'm switching from f4 to h4. :-)

I think probably b1.  The only lines that come to my mind when a piece moves to b1 are in the Yugoslav Attack of the Sicilian Dragon, or maybe sometimes in the Winawer Variation of the French.  I'm not sure, but b1 comes to my mind as the square I, and probably a lot of people, visit the least.

No, they're not main stream openings :) and I prefer Be2 in my sicilian's anyway.  I didn't even think that black might use f4 more often than white which may be.  The KG though - 1...e5 2.f4 used to be the only respectable way to open a game I guess the question is present day chess only though.

h4 is a good guess, and like you said if it's least used as in how often a piece moves there a1/a8 would be good candidates.

Many closed formations like an english often have ideas with Rb1 b4-b5 so maybe a1 is even less used?  Sometimes after 0-0-0 it might be used as part of an attack breaking through or Ka1 as defense, but probably not very often, and if a rook belongs on the a file to begin with usually the player will leave it there and simply open the a file.

If you define it as total length of occupation, then it would probably end up being a square on the 3rd through 6th ranks.

@orangehonda when I was talking about f4 for white vs black, I wasn't clear enough. I meant that white uses f4 less than black uses f5. And so on - for the squares h4 and h5, I think that black uses h5 more often than white uses h4. Let's face it, the game of chess is not symmetrical.

However, the question is which is the LEAST visited of any of the squares.  Overall.  Among everybody.  Even though one person may rarely ever go towards the center, a ton of people use the central squares often enough.  e4, e5, d4, d5, c4, c5, c3, c6, f3, f6, d7, e7, and sometimes f4 or f5 are really common overall over most of the chess-playing population.  g3, g6, g2, g7, c7, c8, e8, and the mating squares are all pretty common, too.  Let us not forget some Fried Liver Attack g5, f7, c2, f2.  Scholar's mate stuff: some h4, h5, g4, it seems to me now that the population of chess players is so varied that it must be extremely tough to find the least visited square on the chess board.

after the a8 rook vacates the square Im guessing thats an uncommon one

 a1 is actually a pretty common square in games of beginners where people hang rooks on a1, or get checkmated on a1.

But if that rook vacates a8 on move 19, then it was visited for the first 19 moves... and if the game ends on move 32, then surely other squares were less visited.

@ ozzie_c_cobblepot:

but what if 'visiting' is when pieces go TO a square, not just rest on it.  For example, Bb7-a8 would be 'visiting' a8.