The 28-year old Austrian defender joined the Hornets from German club Werder Bremen on a free transfer earlier in the summer and despite admitting it hard to leave his old club, is excited about the next phase of his career in the Premier League.
"The decision to leave Werder Bremen was hard, but the decision to come to the Premier League and to come to Watford was very easy," Prodl told the club's official website.
"I met Mr Pozzo and I was impressed with his ideas, so I became interested in trying to make a contract with Watford. I had a good feeling about the people here, and I think it's a good choice to come here."
The centre-back continued: "I know that the German league is a very good league and one of the best in the world, but I don't think you can compare it with the Premier League.
"The passion for the football here, the passion of the fans, the stadiums, and the big clubs you're going to play against, there's nothing better in the world. I'm very excited to get this experience.