Before getting to the article, here are the basic dimensions of a baseball field: 90 feet between the bases and 60 feet 6 inches between the pitcher’s mound and home plate. Outfield dimensions are not standardized. Read on to learn about the history of baseball’s dimensions, as well as Little League dimensions.

There are nine players in a baseball, nine innings in a baseball game and each base is 90 feet apart. Yes, the folks in the Knickerbocker baseball club, who in 1845 started to develop the rules of modern baseball, had a thing for the number nine.

But besides the 90 feet between the bases the rest of the dimensions of a baseball field were developed post-Knickerbocker, and have with a few exceptions been more or less set for the past 120 years.

The most important dimension on a baseball field after the distance between the base is the distance between the pitcher’s mound and home plate, something the Knickerbocker rules never specified. In fact, the original pitcher’s mound was a large box which was 45 feet away from home plate at its closest point. Pitchers of the day, who threw underhanded, could run up to that closest point before release as long as they began their running inside the box.

In 1893, the pitching rubber was moved back to 60 feet 6 inches, where it remains today, and all the running up and throwing underhand nonsense had been eliminated. There has long been rumors that baseball came to 60 feet 6 inches through a clerical error, but the best evidence suggests the distance was an intentional attempt to balance the power between hitter and pitcher.

While pitchers initially pitched off of flat ground, starting in 1903 there was a pitcher’s mound, which could be no higher than 15 inches. After a particularly dominant year for pitchers in 1968 (and the fact that some teams had pitcher’s mounds approaching 20 inches, in violation of the rule) MLB changed the dimensions of the pitcher’s mound, ruling it now had to be no higher than 10 inches, and actively enforcing that rule. The rubber, on which the pitcher has to maintain contact before his throwing motion begins, is six inches front to back and two feet across. The entire mound is 18 feet in diameter.

Home plate is a five sided slab of rubber, which would be 17 inches square if not for its peaked top. On each side of home plate there is a batter’s box, with is 4 feet by 6 feet.

The dimensions of the three bases are 15 square inches.

The dimensions of the outfield in Major League and all levels of baseball are not standardized. In current MLB stadiums the distance from home plate to the fence at the foul line is between 302 and 355 feet. To center it is between 390 and 435 feet. Throughout Major League history there have been been center field fences as deep as 500 feet (The Polo Grounds in New York) and foul line fences as short as 251 feet (Los Angeles Coliseum.)

Youth baseball has different field dimensions than MLB. In Little League the bases are 60 feet apart and the pitcher’s mound is 45 feet from the plate. The minimum an outfield fence can be in Little League is 200 feet.

Baseball fields just don’t magically appear. They need to be built. And then they need to be maintained or nature will reclaim them. Baseball field equipment is used for this construction and maintenance. Learn more about types of baseball field equipment and their functions below.

The bases
It wouldn’t be baseball without the bases, right? Sets of bases run between about $300 and $600. Breakaway bases, which will release from their anchor on hard impact , are used in all of youth baseball, most high school baseball and increasingly in college and the minor leagues. The breakaway bases in youth baseball release with less impact than would be required to dislodge the equipment used with the older age groups. Little League (and softball of just about all ages) uses something called a double first base, which has white half in fair territory and a orange half in foul territory. The defense (first baseman) puts his foot on the white half to try to record an out whereas the offense (baserunner) uses the orange half to try to beat the throw. This set up is to avoid injuries. While not technically a base, a baseball field also needs a pitching rubber, which should run between fifteen and seventy dollars.

Drag mats
Drag mats are giant rakes used by the grounds crew to rake the infield dirt. They can be quite expensive — up to a $800 — and some are designed to be pulled by carts or tractors. There is probably not going to be drag mat at a Little League Game, but you might see them in high school, college and certainly the minor leagues.

Rakes and brooms
Specially designed rakes and brooms for for grooming the infield dirt. They should cost less than $100, making them economical alternatives (as well as compliments)to drag mats.

Dry line markers
Sometimes called chalkers, these push-cart like devices are used draw in the foul lines and other demarcations on a baseball field. While most use chalk, there are also spray marker systems which use white paint to form the lines.

Water removal equipment
There are all sorts of different types of equipment to remove water from a baseball field. They include rollers, non-absorbent squeegees and rain out, a chemical which makes dirt dryer. Water pumps and water pillows, which are placed in a puddle and act to absorb all of its water, can also be used to dry a baseball field prior to a game or during a rain delay.

Field covers

Field covers, or tarps, are used to protect a baseball field when there is no game action or when it has begun to rain. They range greatly in price, from $50 to $1500 depending on their size. Some field covers just go over the base areas and the pitcher’s mound. Others, called full-field covers or winter covers, go over the entire infield area. Some of the more expensive field covers come with a roller which distributes the tarp evenly over the field. Sandbag are typically used to weigh the tarp down.

Foul poles
Foul poles are needed in any baseball field with a wall to determine if home runs are fair or foul. They tend to have a net like area that sits on the fair side and “catches” fair homeruns. The cheapest foul poles cost a few hundred bucks and can be attached to a chain-link fencing. These are fine for Little League, but for a higher level you probably need need proper foul poles, which are going to run somewhere between $3000 and $800 for a set.