These acrylic rods make up the Seed Cathedral, the centerpiece of the U.K. Pavilion at the 2010 World Expo in Shanghai, China. Encased at the tip of each 25-foot-long rod are seeds provided by China's Kunming Institute of Botany. Sixty-six feet tall and consisting of 60,000 rods, the structure took about four months to install at a rate of approximately 536 rods a day. The theme of the U.K. Pavilion emphasizes the importance of incorporating gardens and parks into urban life, and the Seed Cathedral, by English designer Thomas Heatherwick, is meant to specifically highlight the concepts of sustainability and diversity of life. The seeds themselves represent Kew Gardens' Millennium Seed Bank, which aims to accumulate samples of 25 percent of the world's seeds by 2020.