Houston ? Fresh off a high-wire, crowd-pleasing halftime performance at the Super Bowl, Lady Gaga has announced plans for a world tour kicking off this summer. Gaga posted news of the tour on Twitter late on Sunday night. The 48-date Joanne World Tour includes stops in North America, Europe and Brazil. Several of her U.S. dates include performances at baseball stadiums, including Chicago's Wrigley Field and Boston's Fenway Park.