Early years Due to geographical isolation, and very small financial abilities for most of the club's history, the basketball team was not able to compete at a high level for many years, and was not funded properly. Kolossos was the first Greek basketball team located in the
Aegean Sea region.
Rise In 2000, the fate of the team finally changed, when Kostas Kostaridis became the new team President, and took over the reins of the club. Kostaridis changed almost the entire club management, and stated that it was the immediate goal of the team to rise from the
3rd-tier level
Greek B League, to the 2nd-tier level
Greek A2 League, and subsequently, the team did begin to rise up through Greece's club basketball league system. In 2003, head coach
Vassilis Fragkias joined the team, and the ascent up into the
Greek A2 League division commenced. In the 2004–05 season, Kolossos won the championship of the
Greek A2 League, and was therefore automatically
promoted up into the top-tier level
Greek League, the highest professional basketball league in Greece.
Merger with Holargos In the
2018–19 Greek Basketball League season, Kolossos finished in last place in the league. The team was thus facing
relegation down to the second-tier level
Greek A2 League. However, Kolossos merged with
Holargos, and gained their rights to play in the top-tier level Greek League, in the following
2019–20 Greek Basketball League season. ==Arenas==