An ancient Persian unit of itinerant distance. For its modern counterpart, see farsakh.

It was also used by the Greeks (the παρασάγγης), which the Greeks took to be equal to 30 stades (thus about 5.76 kilometers, Olympic measure, or 5.32 km, Attic measure).

sources

The equator divides the earth into two halves from west to east. It represents the length of the earth. It is the longest line on the sphere of the earth, just as the ecliptic and the equinoctal lines are the longest on the firmament. The ecliptic is divided into 360 degrees. The geographical degree is twenty-five parasangs, the parasang being 12,000 cubits or three miles, since one mile has 4,000 cubits. The cubit is twenty-four fingers, and the finger is six grains of barley placed closely together in one row.

Ibn Khaldûn. The Muqaddimah. An Introduction to History.
Franz Rosenthal, translator.
N. J. Dawood, editor and abridger.
Bollingen Series.
Princeton University Press, 1969.
Page 49. Chapter One, Second Prefatory Discussion.

Ibn Khaldûn states that he completed the first version of this work in November 1377. The arabic names of the units which Rosenthal has
translated are: parasang, ; cubit, ; finger, .