genesis 5:4( a chapter recap of the life of adam) - And the days of Adam after his fathering Seth came to be eight hundred years. Meanwhile he became father to sons and daughters.

genesis 4: 17- (vrs 16 is when he went to nod) Afterward Cain had intercourse with his wife.

Cain was already married to a daughter of adam and eve, she went with him to NOD.

The hebrew NOD simply means land of fugitives.