very cosmopolitan; very international
Describes a place, event, or atmosphere that is rich in international character, with diverse cultural influences.
This town is very cosmopolitan, and you can enjoy cuisine from various countries.
A very international group of members gathered.
国際的 means 'international' in a neutral sense, while 国際色豊か emphasizes a rich, vibrant international flavor or atmosphere.
Compound of 国際色 (international flavor/character) and 豊か (abundant, rich).