Complex sentence: When the station and its neighbour New Holland Pier were closed they were replaced by a wholly new New Holland station south of the former, which formed an integral part of the Barton Line which was still running in 2015.
Split into simpler sentences: When the station and its neighbour New Holland Pier were closed they were replaced by a wholly new New Holland station south of the former. This new station formed an integral part of the Barton Line which was still running in 2015.