On stardate 34180.7, Starfleet held a tournament on Risa. The winner was Jean-Luc Picard, who was awarded the Silver Spade. A certificate containing this information was included in the Picard family album. (Star Trek Nemesis)
While only seen during the reappearance of the family album in Star Trek Nemesis, the page containing the award was already produced together with the rest of the album for Star Trek Generations. A closer look of the certificate was included in the DVD special features of that film.
Picard visited Risa in "Captain's Holiday", set around stardate 43745.2. However the stardate on the certificate suggests an earlier visit, before commanding the Enterprise. Although Riker starts pitching the planet to Picard as if he is not familiar with it, nothing in the episode categorically rules out the idea that Picard has been there before.