"They were hugging and kissing as much as possible," an onlooker at Charles de Gaulle airport tells Us Weekly. "They got airline priority to get through customs and security, but were in no hurry. They were just so happy to be together and starting a visit to Paris as a couple."
The "Wanderlust" co-stars were photographed arm-in-arm under the same umbrella as they strolled next to the Tuileries Gardens, on the banks of the River Seine next to the Louvre Museum on Monday morning.
In the May issue of Marie Claire Australia, Aniston, 43, opened up about what she loves most about Theroux. "He's a protector, for sure," she said. "He's just a good human being, and so funny."
And Theroux is a big change compared to the actress' exes like Brad Pitt and John Mayer. "Their relationship is completely different than any of her other ones," an Aniston pal told Us in 2011. "Everything about Justin feels right."
Keep clicking to see photos of Jen and Justin in Paris ...