Adriatic Croatia International Club, commonly referred to as ACI Club or simply ACI, is a Croatian nautical tourism company based in Opatija which operates a marina chain along the Croatian part of the Adriatic coast. From the initial 16 marinas opened in 1986 they expanded to 22 in 2016, which makes it the largest chain of marinas in the Mediterranean as of 2016. ACI is also known for organizing the annual match racing sailing regatta called the "ACI Match Race Cup", first held in 1987.