The Indian League Division 1, also known as the I-League, is the top professional football league in India. It was established in 2007 and is organized by the All India Football Federation (AIFF). The league consists of 10 teams that compete in a round-robin format, with each team playing against each other twice. The most successful team in the history of the league is Dempo SC, who have won the title on three occasions. An interesting fact about the I-League is that it is one of the oldest football leagues in Asia.