The 30-year-old, who made his France debut in the 2008 RBS Six Nations, spent six seasons at the Basque club.
Barcella has been capped 20 times in total by his country, the last of those coming in the 2011 World Cup Final, and hopes his move to Toulon will lead to future international recognition although he concedes it may take a little while to settle in to his new surroundings.
"It was hard to leave," Barcella told RugbyRama.
"But we had a disastrous season. We turned over a new page with Damien Traille leaving and Dimitri Yachvili. It was the end of an era. I want to see something else.
"It will take time to adapt and I must work hard because there is a change of level.
"The competition is strong. In my position, there are three top players plus Andrew Sheridan if he returns. But I look forward to getting to know the group and representing Toulon.
"The climate is not the same as Biarritz. I saw the club facilities with the training centre, the weights room - there is everything on-site; it is awesome."
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