1 Chronicles 26:13-16

13They cast lots for each gate, according to their families, young and old alike.

14The lot for the East Gate fell to Shelemiah.1 Then lots were cast for his son Zechariah, a wise counselor, and the lot for the North Gate fell to him. 15The lot for the South Gate fell to Obed-edom, and the lot for the storehouses to his sons. 16The lots for the West Gate and the Shallecheth Gate on the ascending highway2 fell to Shuppim and Hosah.

There were guards stationed at every watch.