Ignition apparatus for an internal combustion engine

A cylindrical type ignition apparatus housed in a spark plug hole of a cylinder of an internal combustion engine is disclosed. A center core, a primary coil, a secondary core and a side core are provided, and a closed magnetic path is formed by connecting magnetically the center core and the side core by a core on a high voltage side and a core on a low voltage side, or a semi-closed magnetic path is formed by connecting magnetically the center core and the side core by a core on a low voltage side.