Princess Cruises is celebrating the first birthday of Royal Princess today (June 13), which was launched in Southampton, England during a christening by Her Royal Highness The Duchess of Cambridge. Guests currently sailing aboard Royal Princess will be treated to some special festivities marking the occasion including a “Royal Ball Birthday Party” in the ship’s showpiece atrium with a birthday sing-a-long, balloon drop and celebratory cake. During the past 12 months Royal Princess has travelled 120,000 miles and carried 150,000 guests. The 3,600-passenger ship has set sail on 44 cruises, and visited 39 ports in 20 countries throughout the Mediterranean and Caribbean.