The Well of Harod or Spring of Harod (Hebrew: עין חרוד, Ein Harod) is a spring near the two kibbutzim called Ein Harod in the Jezreel Valley in Israel. In Arabic it is called `Ain Jalut (عين جالوت) meaning the Spring of Goliath.
It is mentioned in the Book of Judges, chapter 7, where it is said that Gideon dismissed 22,000 potential warriors who were "fearful and afraid" and then chose 300 men to fight with him according to how they drank water from the Well of Harod. Anglican bishop Charles Ellicott and Presbyterian theologian Albert Barnes both suggest that "Harod" means "trembling", "with an obvious allusion to the timidity of the people (chareed, Judges 7:3)".
Yaqut al-Hamawi mentions Ain Jalut as "a small and pleasant town, lying between Nablus and Baisan, in the Filastin Province. The place was taken by the Rumi (Crusaders), and retaken by Saladin in 579 (1183 CE)."
In the Battle of Ain Jalut in 1260, the Mamluks defeated the Mongol army of Hulagu Khan which was under the command of Kitbuqa.
According to the Palestine Exploration Fund's Survey of Western Palestine 1882, Victor Guérin stated that the rock from which the fountain springs has been artificially hollowed into a cavern.
The well is now a national park called Ma'ayan Ḥarod.
Wikipedia

See Bædeker (1898) Route 22 page 259 and Route 27 page 278 ('Ain Jâlûd)

Murray Route 22 page 354 ('Ain Jâlûd)

The large fountain of ’Ain Jâlûd at the northern base of Gilboa, 1/2 h. E. of Zer’în, deserves a visit, for it is a noted spot in sacred history—the scene of one of the most memorable victories, and of one of the most memorable defeats, in the annals of Israel....