Newport Arch is what remains of the northern gate of the Roman fortress of Lindum Colonia — a 3rd-century stone gateway with a single pedestrian arch and two larger vehicular arches, originally part of a much larger gate complex. The footprint of the arch sits where the modern road has worn down nearly two metres below the Roman ground surface, giving the structure its slightly buried look.
It is one of only a handful of Roman archways anywhere in Europe still in regular vehicular use — the modern road runs underneath. Newport Arch is a short walk uphill from the cathedral square and can be visited freely at any time; combine it with a walk along the still-visible course of the city walls.