Genesis 8:13

And it came to pass in the six hundredth and first year, in the first month, the first day of the month, the waters were dried up from off the earth: and Noah removed the covering of the ark, and looked, and, behold, the face of the ground was dry.

Cross-reference

Genesis 7:11 Historical context

Genesis 7:11 gives the exact start date of the flood; Genesis 8:13 gives the exact end date, together framing the deluge timeline.

Genesis 7:6 Historical context

Gen 7:6 gives Noah's age at flood start (600), providing the chronological anchor for the date in 8:13 (601st year, 1st month).