Complex sentence: Assurbanipal took an active part in the restoration of sanctuaries in the South, a stela now in London commemorates his help in restoring Esagila (the tower of Babel), another tells of how he restored the Nabu-temple in Borsippa.
Split into simpler sentences: Assurbanipal took an active part in the restoration of sanctuaries in the south. A stela now in London commemorates his help in restoring E-sagila (the tower of Babel), another tells of how he restored the Nabu-temple in Borsippa.