The Roman Walls which once surrounded Córdoba, Spain, were built after the Romans captured the city in 206 BC, making it part of the Roman Republic.
Built as fortifications soon after the Romans captured Córdoba, the walls stretched some 2,650 m, completely surrounding the city. They consisted of carefully cut stone with an outer wall of up to 3 m high and a 1.2 m inner wall flanking a gap 6 m wide filled with rubble. There were several semicircular towers along the walls. When the city received the status of Colonia Patricia under Augustus, the southern wall was demolished in order to extend the city limits to the river. Vestiges remain in the Alcázar, near the Roman bridge, and flanking the Avenida de la Ribera. The walls next to Calle San Fernando and Calle Cairuán (restored in the 1950s) also have a base from this period. A section of the Roman wall can be seen from the street next to the Roman temple.
Roman gates included the Porta Principalis Sinistra (later Puerta de Gallegos) on the west side not far from the Roman mausoleum. The arches next to the Puerta de Sevilla to the east are part of a Roman aqueduct.
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.