[by the way how big is 5 rod in mtr by mtr
Found this on Wikipedia.
The rod or perch or pole is a surveyors tool[1] and unit of length equal to 5 1⁄2 yards, 16 1⁄2 feet, 1⁄320 of a statute mile or one-fourth of a surveyor's chain and 5.0292 meters. The rod is useful as a unit of length because whole number multiples of it can equal one acre of square measure. The 'perfect acre'[2] is a rectangular area of 43,560 square feet, bounded by sides 660 feet by 66 feet long (660 ft long × 66 ft wide), or 220 yards by 22 yards long (220 yd/ long × 22 yd wide), or 40 rods by 4 rods long. Thus, an acre is 160 square rods. Since the adoption of the international yard on 1 July 1959, the rod has been equal to exactly 5.0292 meters.
The agricultural surveying tool was a chain. This had 100 elongated links with a small disc attached every 25 links to mark the pole. 4 poles in a chain, 10 chains in a furlong and 8 furlongs in a mile. A furlong was the standard length of a furrow in the old field systems. 1 furlong X 1 furlong is 10 acres. What a beautiful simple system. Then someone decided yards should be used, 3 feet = 1 yard, 12 inches = 1 foot, 36 inches =1yard, and we had 4840 square yards to an acre. What a mess. Then we went metric, which is in fact quite good with multiples of 10, but a hectare 2.471 acres. Agriculture, and Councils on allotments, have sensibly stuck with the old way.
