The members of One Direction have proved that they're still big kids at heart by having a magic time during a trip to a Harry Potter theme park.

And Louis Tomlinson even dressed up in a Gryffindor house uniform for the experience at The Wizarding World Of Harry Potter, at Universal's park in Orlando, Florida.

things I never knew i needed until now: Louis dressed as a Harry Potter character pic.twitter.com/MvPXuvPuAe

— mel (@calumnesia) November 18, 2014

The 22-year-old singer was happy to pose with fans at the attraction, appearing even more excited than some of them in selfies that have emerged.

And bandmate Liam Payne took to Instagram to share a video clip of himself "disappearing" through a wall and emerging again with arms aloft.

Unfortunately, 1D's very own Harry doesn't appear to have joined in the fun.

The boys are in the US promoting their new album FOUR - and have been involved in a controversy after a TV presenter suggested Zayn Malik missed the trip due to "substance abuse".