How do I get to Cinnabar island in Pokemon soul silver? The path is blocked and under construction?

The guys say it's under construction and that if I want to go to Cinnabar, then I have to go to pallet town ,which I have no way to get to. The only towns/cities I can go to in this region are; Cerulean, Saffron, Celadon, Lavender town, Vermilion city , and Fuschia city. How can I get past this?