 In October "Columbia Rediviva" and crew began building Fort Defiance and a small craft called as they prepared to ride out the winter in harbor.After wintering on Vancouver Island, Gray set sail again on April 2, 1792 when he left the American trading post of Clayoquot on Vancouver Island.On this journey aboard "Columbia Rediviva" Gray noticed muddy waters flowing from shore and decided to investigate his belief that it might be the "Great River of the West".