Canadian submarine "Victoria" docks at Canada Place in Vancouver, Canada, April 25, 2013. The four-day Vancouver Port visit event showcases several vessels from the Royal Canadian Navy and United States Navy which are opened for public tour.(Xinhua/Liang Sen)

Canadian submarine "Victoria" docks at Canada Place in Vancouver, Canada, April 25, 2013. The four-day Vancouver Port visit event showcases several vessels from the Royal Canadian Navy and United States Navy which are opened for public tour.(Xinhua/Liang Sen)