Stockton International Riverside Festival 2026 kicks off this weekend, with more than 100 free performances taking place across three days from Friday, July 31, to Sunday, August 2. Mirage at SIRF Carnival. (Image: Stockton Borough Council)The annual festival is one of the region's biggest cultural events, bringing together street theatre, dance, music, circus acts and interactive art installations. Euforia at SIRF Carnival. The festival village will offer street food, drinks, live music and seating areas where people can take a break between performances.