Complex sentence: The northern part of the famous Île de la Jatte in the river Seine, where French impressionist painters created many of their masterpieces, is part of the commune of Levallois-Perret.
Split into simpler sentences: The northern part of the famous Île de la Jatte in the river Seine, is where French impressionist painters created many of their masterpieces. It is part of the commune of Levallois-Perret.