Travis Kelce Attends Cannes Lions Festival With Brother Jason Kelce

Travis Kelce joined his brother Jason Kelce for a trip across the pond to France -- this right after lighting it up in Nashville ... just proving that the dude's real busy in the off-season.

Despite their whirlwind schedule, the Kelce brothers looked relatively fresh while walking the streets in Cannes as they hit up the Cannes Lions International Festival of Creativity Thursday -- where they dished on their fame during a scheduled event ... more on that later.

Travis was strolling with his security team instead of his superstar GF, Taylor Swift ... who's busy touring in the UK right now. Jason, meanwhile, was spotted out with his wife, Kylie.

Everybody was rocking summer gear ... and JK specifically looked ultra relaxed and in vacay mode -- wearing an open Hawaiian-style shirt, shorts and even flip-flops.

As we mentioned, the siblings were in town to speak at the festival -- for a gig called "The Kelce Effect: Exploring New Heights With Travis and Jason Kelce" ... where they delved into their podcast, "New Heights," and their unique dynamic as co-workers and brothers.

Trav traded in his party hat for some Euro workwear after his wild night in Nashville. Remember ... he was just there, alongside George Kittle and Greg Olsen for their "Tight End University" event at Brooklyn Bowl, where he took the stage/riled up the crowd.

From globe-trotting escapades to his headline-making romance with Taylor ... TK's been a man about town lately -- and he's arguably done more traveling this year than ever before.