Complex sentence: Several significant snowfalls have been recorded since 1900, the most significant on 5 July 1900, when snowdrifts were over six feet deep in parts of the Blue Mountains.
Split into simpler sentences: Several significant snowfalls have been recorded since 1900. The most significant falls were recorded on 5 July 1900 when snowdrifts were over 6 feet deep in parts of the Blue Mountains.