Complex sentence: This is a difficult stage, incorporating of cobblestones in seven cobbled sectors over the last, culminating in the Arenberg Trench, which is known for being one of the most difficult sectors used in Paris-Roubaix.
Split into simpler sentences: This is a difficult stage, incorporating of cobblestones in seven cobbled sectors over the last. The cobbles culminate with the Arenberg Trench, which is known for being one of the most difficult sectors used in Paris-Roubaix.