Complex sentence: Tadoussac is the east terminus of the Baie-Ste-Catherine/Tadoussac ferry, which offers free and frequent service across the Saguenay River and is part of Quebec Route 138 and the main link to Sept-Îles.
Split into simpler sentences: Tadoussac is the east terminus of the "Baie-Ste-Catherine"/ "Tadoussac" ferry, which offers free and frequent service across the Saguenay River. It is part of Quebec Route 138 and the main link to Sept-Îles.