Complex sentence: The station is named after a nearby bridge over the River Ingrebourne, which was the boundary between the ancient parishes of Hornchurch and Upminster; and is located on the western "Hornchurch" side.
Split into simpler sentences: The station is named after a nearby bridge over the River Ingrebourne. The river was the boundary between the ancient parishes of Hornchurch and Upminster and the station is located on the western "Hornchurch" side.