Complex sentence: Not far from Sukhothai are the Si Satchanalai historical park and the Kamphaeng Phet Historical Park, both were cities within the former Sukhothai kingdom and of the same time period.
Split into simpler sentences: Not far from Sukhothai are the Si Satchanalai historical park and the Kamphaeng Phet Historical Park. Both were cities within the former Sukhothai kingdom and of the same time period.