Complex sentence: The medieval history of Tiruchirappalli begins with the reign of the Pallava king Mahendravarman I, who ruled over South India in the 6th century AD and constructed the cave-temples within the Rockfort.
Split into simpler sentences: The medieval history of Tiruchirappalli begins with the reign of the Pallava king Mahendravarman I, who ruled over South India in the 6th century AD. Mahendravarman constructed the cave-temples within the Rockfort.