Complex sentence: The anniversary of the Ponorogo regency is commemorated on 11 August, because on 11 August 1496, Bathara Katong, the first leader of Ponorogo, went from Old Town to Central City to Ponorogo.
Split into simpler sentences: The anniversary of the Ponorogo regency is commemorated on 11 August. On 11 August 1496, Bathara Katong, the first leader of Ponorogo, went from Old Town to Central City to Ponorogo.