Nehemiah 6:1, 15

Now it came to pass, when Sanballat, and Tobiah, and Geshem the Arabian, and the rest of our enemies, heard that I had builded the wall, and that there was no breach left therein; (though at that time I had not set up the doors upon the gates;)

So the wall was finished in the twenty and fifth day of the month Elul, in fifty and two days.