In a solid cylinder, the frequencies of the mode branches of elastic waves decrease as the diameter of a cylinder increases. This feature can be used to control the mode conversion in an elastic waveguide comprising solid cylinders with different diameters. In this study, we experimentally investigated a waveguide with a cylindrical island that is connected to two cylinders via pillars on both ends of the island. A localised wave can be generated in the island which involves resonant transmission and reflection caused by the Fano effect.