What does one acre measure or represent?

Answer 1

One acre is a measure of area which is equal to 4840 sq yd or 1/640 square mile. It does not matter what shape it has.

Historically an acre was the amount of land a set of oxen could plough in 1 day. A rectangular piece of land 220 yards (or 1 furlong) long by 22 yards (or 1 chain) wide has an area of 1 acre.

Answer 2

An acre is defined by square feet. No matter the shape, "one acre" must ALWAYS contain as its area is exactly 43,560 square feet.

So for example, take a piece of paper and somewhere along the outside edge on the left nearer the bottom, draw a small circle on it to represent a boulder--a big rock. In another spot near the edge near the top, on the left, draw a tree. Now, somewhere in the right area about halfway down the page, draw a thin rectangle for a post. Lastly, across the bottom, draw a fenceline +++. Next, draw a short line near the top of the page for a railroad track. Now, your goal is to use those natural and manmade landmarks to draw the outline of your "property" (land). Make a zig-zag line from the boulder going down to the fence. Draw a line from the boulder to the tree. Pretend the "railroad" is along the edge of your property but is not part of your property, so draw a line under it. From the right side of your line at the railroad tracks, go down to the "post", then, draw from the "post" to the fenceline. You should now have a strange-looking shape (NOT a square).

Most land is NOT divided into a square shape. One part can be narrow or thin. Another part can be very crooked. Historically, people went around boulders, trees, creeks and anything that sat in the way. So I might have the tree on "my" property but you might have the "boulder" on your property.

When men wanted to know how much land they owned, they called on a surveyor. The surveyor measured the land in square feet-- the total of the square feet. So I might own 1/2 acre and 2 perches; you might own 1 acre and 20 perches. As long as the area is exactly 43,560 square feet, that is exactly one acre--no matter how the land is shaped.

Answer 3

One acre is the name given to 43,560 square feet of area, or 4,840 square yards
of area, or 0.0015625 (1/640) of a square mile of area.

'One acre' refers only to the area inside some boundary. It says nothing about
the shape of the boundary. If it is the area of a circle, then the circle's diameter
is about 235.5 feet. If it is the area of a square, then the square's sides are about
208.7 feet long. If it is the area of a rectangle that is 15 feet wide, then the rectangle
is 2,904 feet long. etc.