Complex sentence: In 1913, the plague broke out in Java and during this period Old Batavia, with its abandoned moats and ramparts, experienced a new boom as the commercial companies were re-established along the Kali Besar.
Split into simpler sentences: In 1913, the plague broke out in Java. Also during the period, Old Batavia abandoned moats and ramparts experienced a new boom, as the commercial companies were re-established along the Kali Besar.