Calais Port would be a huge French port located in Calais, France where Mater would go as part of his mission. The scene got unproduced for unknown reasons and presumably got replaced with the Paris scenes.
"At one point we had a scene that was to take place at a huge port in Calais. A lot of that environment would just look like a functional machinery for humans. But in the Cars world, it was an enormous international marketplace with a great New York -like vibe. Cargo ships, sailboats, yachts, trucks, trains, cranes - it was a teeming and energized environment, with everything in transport from one place to another."
- Brad Lewis about Calais in book The Art Of Cars 2