Pen Dinas is the name of a large hill just south of Aberystwyth where an extensive Iron Age, Celtic hillfort of international significance is situated.
The hillfort actually consists of two separate forts built many years apart, which were later combined to form a larger structure. The first fort to be constructed was on the lower northern summit. It consists of an outer ditch and inner rampart of rubble. It would originally have been surmounted by a wooden palisade. The main gateway is on the western side and is formed by a stone lined gap in the ditch and bank.
After this first fort was eventually abandoned several decades passed before work began on a new fortification on the higher summit to the south. This second site is better protected by a steeper slope on the western side. To the south and east huge terraced earth works were built faced with shale which would again have been topped with a wooden palisade. Entrance into the southern fort is via gateways to the north and south. They are both formed of narrow passageways through the earthworks and would also have had timber bridges to cross the ditches. The northern gateway is kinked to the left, probably to aid defence by slowing down attackers.
Eventually the southern fort too became derelict and there is evidence that some of the wooden structures by the northern gateway were burnt. This could be following a hostile raid on the fort or because lack of resources lead to its abandonment. However, sometime later the defences of the southern fort were rebuilt this time to a different layout.
The final phase in the fort's construction was the refortification of the northern section and the construction of banks and ditches to connect the two forts together thereby enclosing the entire hill top. The coming of the Romans to the area in about 74 AD may have led to the forcible abandonment of the fort or it may have fallen from use before then but the only evidence from the Roman period is an early 4th-century coin hoard of Roman currency possibly left as an offering to a shrine on the hill.
References:Visby Cathedral (also known as St. Mary’s Church) is the only survived medieval church in Visby. It was originally built for German merchants and inaugurated in 1225. Around the year 1350 the church was enlarged and converted into a basilica. The two-storey magazine was also added then above the nave as a warehouse for merchants.
Following the Reformation, the church was transformed into a parish church for the town of Visby. All other churches were abandoned. Shortly after the Reformation, in 1572, Gotland was made into its own Diocese, and the church designated its cathedral.
There is not much left of the original interior. The font is made of local red marble in the 13th century. The pulpit was made in Lübeck in 1684. There are 400 graves under the church floor.