The county's landmarks span many centuries, ranging from the Six Hills in the new town of Stevenage built by local inhabitants during the Roman period, to Leavesden Film Studios. The volume of intact medieval and Tudor buildings surpasses London, in places in well-preserved conservation areas, especially in St Albans which includes some remains of Verulamium, the town where in the 3rd century an early recorded British martyrdom took place. Saint Alban, a Romano-British soldier, took the place of a Christian priest and was beheaded on Holywell Hill. His martyr's cross of a yellow saltire on a blue field is reflected in the Hertfordshire flag and coat of arms.