Complex sentence: The current dam is close to the ruins of the Great Dam of Marib, dating from around the sixth or seventh century BCE, it was one of the engineering wonders of the ancient world and a central part of the south Arabian civilization around Marib.
Split into simpler sentences: The current dam is close to the ruins of the Great Dam of Marib, dating from around the sixth or seventh century BCE. It was one of the engineering wonders of the ancient world and a central part of the south Arabian civilization around Marib.