Watch City Steampunk Festival, previously known as International Steampunk City and the Watch City Festival, is the oldest annual open-air, indoor/outdoor steampunk festival in the United States and is held in Waltham, Massachusetts. The Watch City Festival invented a new model of science fiction convention in which the larger community was deliberately engaged by holding events and programing in city spaces and local businesses often free to the public. It began in 2011 as a fundraiser by and for the benefit of the Charles River Museum of Industry and Innovation, which suffered significant flood damage in March 2010.