Complex sentence: The town is also served by Southeastern train services to/from London, via either North Kent and Medway or Canterbury and High Speed 1 and is unusual in the sense that trains to London can run either way through the station.
Split into simpler sentences: The town is also served by Southeastern train services to/from London, via either North Kent and Medway or Canterbury and High Speed 1. It is unusual in the sense that trains to London can run either way through the station.