Complex sentence: Belfast is also connected with Carrickfergus and Larne, Portadown, Newry and onwards, via the Enterprise service jointly operated by N.I.R. and Iarnród Éireann, to Dublin Connolly.
Split into simpler sentences: Belfast is also connected with Carrickfergus and Larne, Portadown and Newry. The jointly operated Enterprise run by N.I.R. and Iarnród Éireann, connecting Belfast Central to Dublin Connolly.