'Tower' in the Bible

Now the watchman was standing on the tower in Jezreel, and he spied the company of Jehu as he came, and said, I see a company. And Joram said, Take a horseman, and send to meet them, and let him say, Is it peace?

And the children of Israel did secretly things that were not right against Jehovah their God: and they built them high places in all their cities, from the tower of the watchmen to the fortified city;

He smote the Philistines unto Gaza and the borders thereof, from the tower of the watchmen to the fortified city.