The Blank Space hitmaker brought her 1989 tour to her home state of Pennsylvania on Saturday (06Jun15), and she treated fans to a special performance.

In video footage of the show, Swift tells the crowd, "Honestly, the last two times that I've played here, I've said to myself, 'That is an incredible crowd. That crowd is located in the state where I grow up. Every time I go and see them, they go so far above and beyond, I need to do something special for them the next time I come back'... I’ve been in the music industry for about 10 years, and one of the first bands I ever met was one of the nicest bands and one of the most talented, and they’ve always been the coolest people. So, I know you guys have a river around Pittsburgh, and I wonder if you ever go out on a pontoon boat?"

Swift then invited the country music foursome onstage to sing their hit song Pontoon with their pop star friend, as dancers surrounded them in swim gear and paddles.

Later, Swift took to Instagram.com to share backstage clips of her singing Little Big Town's recent hit Girl Crush along with the band, as well as up-and-coming singer Rachel Platten, country singer Kelsea Ballerini, and Swift's opening act Vance Joy.

The jam session also included renditions of Ballerini's Yeah Boy and Platten's Fight Song singles.