Dover Downs Sportsbook Review Dover Downs sportsbook is a great place for Delaware sports bettors to get in on the action. Having legal sports betting since the middle of 2018, Dover Down has become the most popular sportsbook in the state. Dover Downs sportsbook is home to a bevy of betting lines across multiple sports for residents and tourists alike to wager on. There are endless options when it comes to sports betting at Dover Downs Sportsbook. Delaware residents and tourists in the area are sure to be impressed by the massive size of the facility.