Taylor Swift is currently in Europe on her "1989" tour. After performing in London on June 27th (local time), the singer took time out of her busy schedule to explore the city, posting a photo of her visit on Twitter. The photo, captioned "Little-known fact: Karlie is an unofficial London historian and tour guide," was taken on a boat on the River Thames. Taylor's best friend, model Karlie Kloss, is in the middle, with Taylor hugging her boyfriend Calvin Harris on the right, Gigi Hadid and her boyfriend Joe Jonas on the left, and a beautiful sunset and Tower Bridge in the background. Carly and Gigi appeared on stage with Cara Delevingne, Kendall Jenner, Martha Hunt, and tennis player Serena Williams during Taylor's performance of "Style" at Hyde Park on the 27th, and the crowd went wild. Emma Watson was also seen backstage, although she did not appear onstage.