Complex sentence: Gasr Banat or Gasr Isawi is the location of an Ancient Roman centenarium or "perched" oppidum and a semi-permanent camp for nomads in Libya.
Split into simpler sentences: Gasr Banat or Gasr Isawi is an archaeological site and the location of an Ancient Roman centenarium or "perched" oppidum. The area is also used as a semi-permanent camp for nomads in Libya.