Castles were built by the Normans after the Norman Conquest of 1066 to control the local population. They were often located on high ground, overlooking the town. The castle was the seat of power for the local lord, and it was also used as a military base.
Cathedrals were built by the Roman Catholic Church. They were often located in the center of town, and they were used for religious services, as well as for social and cultural events. The cathedral was the most important building in the town, and it was a symbol of the power of the Church.
Marketplaces were located in the center of town. They were used for buying and selling goods, and they were also used for social gatherings. The marketplace was an important part of the local economy, and it was a place where people from all walks of life could come together.