Introduction
Enoch is a son of Cain, notable as the namesake of the first city mentioned in the Bible, which Cain is recorded as building and naming after him.
Note: this Enoch, of Cain's line, is a different figure from the Enoch of Seth's line, son of Jared, who "walked with God" and was taken without dying; the two share a name but are distinct individuals.
Family
The first city
Genesis 4:17 records that Cain, after being cursed to wander, built a city and named it after his son Enoch, the first city mentioned in the biblical text, though its precise location is not given.
In the Cainite genealogy
Enoch is the father of Irad, continuing the genealogical line of Cain given in Genesis 4, distinct in form and much shorter than the parallel Sethite genealogy in Genesis 5, down to Lamech and his children.