Complex sentence: Newtowncunningham's long main street once formed part of the N13 trunk road that connects Letterkenny with Derry, meaning that the village's shops and businesses could thrive on custom from passing traffic.
Split into simpler sentences: Newtowncunningham's long main street once formed part of the N13 trunk road that connects Letterkenny with Derry. Mostly located along this long main street, the village's shops and businesses could thrive on a readymade stream of passing traffic.