Complex sentence: Castell Arnallt (Castle Arnold), located below Abergavenny and near modern-day Llanover in the Usk Valley of Monmouthshire, Wales, was a fortification believed to have been the site of the palace of the Kings of Over Gwent.
Split into simpler sentences: Castell Arnallt (Castle Arnold), located below Abergavenny and near modern-day Llanover in the Usk Valley of Monmouthshire, Wales. Castell Arnault was a fortification believed to have been the site of the palace of the Kings of Over Gwent.