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In the Bible, it is not as precisely defined as other Biblical measurements of distance; the distance has been estimated from 32 to 40 kilometers (20 to 25 miles). Judges 19 records a party of three people and two mules who traveled from Bethlehem to Gibeah, a distance of about 10 miles, in an afternoon. Porter notes that a mule can travel about 3 miles per hour, covering 24 miles in an eight-hour day.
In translation by J.B. Bury (Priscus, fr. 8 in Fragmenta Historicorum Graecorum) We set out with the barbarians, and arrived at Sardica, which is thirteen days for a fast traveller from Constantinople. From Constantinople-Istanbul to Sofia is 550–720 km distance at a pace between 42 and 55 km /day.
Based on a comprehensive review of references in Herodotus, Geus  concludes that "Herodotus has a very well-defined notion of what distance a traveller can cover under normal circumstances in a day (between 150 and 200 stades or roughly, between 27 and 40 kilometres)," though he cites some exceptional examples of over 100 km per day.
- Numbers 11:31
- 1 Kings 19:4
- International Standard Bible Encyclopedia, article "Day's Journey"
- Klaus Geus, "A Day's Journey in Herodotus' Histories", in: Klaus Geus and Martin Thiering (Eds.), Common Sense Geography and Mental Modelling, Berlin: Max-Planck-Institut für Wissenschaftsgeschichte, 2012, 110–118