How can I keep my Backyard chickens in my yard?

I live in what's "technically" the city, even though I'm sitting on about 40,000 sq ft of land. I bought out the lots surrounding my little two bedroom so, I have plenty of space for all my critters. I also have a four ft fence that goes around my entire house. However, my silver campine rooster keeps escaping the yard and getting into trouble. Yesterday he had two cats chase him down the street because he got out. I guess I would just like to know if there's any ideas for height of a fence or any other ways I could keep him in my yard. I only have one neighbor who minds him, and he makes sure his kids torment my chicken if he gets out. This needs to stop, I don't want my chicken hurt, I love him too much. Thanks for the help.