PHOTOS – Katy Perry & John Mayer: Sweat Session With Allison Williams!

Katy Perry and John Mayer were all smiles as they held-hands while taking a hike on Wednesday (March 6) in the Hollywood Hills.

The 28-year-old singer was joined by pal ‘Girls‘ star Allison Williams and her boyfriend, CollegeHumor CEO, Ricky Van Veen.

Looks like the foursome was having a great time as they were seen laughing and giggling during their hike.

Last month, Katy and Allison attended the Grammys together.