Millennium Dome. View of the Millennium Dome in London, England, with the River Thames in the background. It is the largest dome in the world and will contain the Millennium Experience, a huge exhibition to celebrate the arrival of the year 2000. The exhibition has 14 themed zones dealing with topics like play, faith, business and the body. The 2 mm thick roof, made of teflon- coated glass fibre fabric, is supported by 70 km of steel cables attached to twelve 100 metre high masts. Rainwater falling onto the roof will be collected for use in the Dome's toilets. Also seen in the background at upper right is the Canary Wharf complex. Photographed in early 1999.