Rideau Hall has been the official residence and workplace of Canada's governor-general since 1867 and is considered to be the symbolic home of all Canadians. The public is welcome to wander the 32 hectares (79 acres) of beautiful gardens and forested areas, and visit the greenhouse -- and for that reason alone, the place is worth a visit; the grounds are exceptional. Outdoor concerts and cricket matches are held in the summer, and there's ice skating on the pond in winter. Free guided tours of the staterooms of the residence are offered; hours vary throughout the year, although in peak tourist season in the summer, there are self-guided tours every morning and guided tours in the afternoons, approximately 45 minutes long. The Governor General's Awards are presented here annually, honoring Canadians for extraordinary accomplishments, courage, and contributions to science, the arts, and humanity. Two major events are held annually for the public -- the Garden Party in June or July and the Winter Celebration. The Ceremonial Guard is on duty at Rideau Hall during July and August. The first Changing of the Guard Ceremony, held in late June, features a colorful parade led by a marching band. Relief of the Sentries is a ceremony performed hourly during the summer, 9am to 5pm, and is always popular with young children. The visitor center, operating daily between May and October, has family activities, a play structure, and hands-on activities for children.