"Stadia (unit of length)" redirects here. For the land surveyor's device, see Stadia rod. For other uses, see Stadion (disambiguation).

The stadion (Greek: στάδιον;[1] Latin: stadium), formerly also anglicized as stade, was an ancient Greek unit of length, based on the length of a typical sports stadium of the time. According to Herodotus, one stadion was equal to 600 Greek feet (pous). However, the length of the foot varied in different parts of the Greek world, and the length of the stadion has been the subject of argument and hypothesis for hundreds of years.[2][3] Various hypothetical equivalent lengths have been proposed, and some have been named.[4] Among them are:

Stade name Length (approximate) Description Proposed by
Itinerary 157 m used in measuring the distance of a journey.[5] Jean Antoine Letronne, 1816[2]
Olympic 176 m 600 × 294 mm Carl Ferdinand Friedrich Lehmann-Haupt, 1929[4][6]
Ptolemaic[7] or Attic 185 m 600 × 308 mm Otto Cuntz, 1923;[4][7] D.R. Dicks, 1960[3][8]
Babylonian-Persian 196 m 600 × 327 mm Lehmann-Haupt, 1929[4][6]
Phoenician-Egyptian 209 m 600 × 349 mm Lehmann-Haupt, 1929[4][6]

An empirical determination of the length of the stadion was made by Lev Vasilevich Firsov, who compared 81 distances given by Eratosthenes and Strabo with the straight-line distances measured by modern methods, and averaged the results. He obtained a result of about 157.7 m.[2]

Which measure of the stadion is used can affect the interpretation of ancient texts. For example, the error in the calculation of the circumference of the Earth by Eratosthenes[9] or Posidonius is dependent on which stade is chosen to be appropriate.