Complex sentence: Ceremonial inauguration of Gdynia as a temporary military port and fishers' shelter took place on 23 April 1923, and the first major seagoing ship arrived on 13 August 1923.
Split into simpler sentences: Ceremonial inauguration of Gdynia as a temporary military port and fishers' shelter took place on 23 April 1923. The first major seagoing ship arrived on 13 August 1923.