Cathedrals were often big and very beautiful churches. They were made of stone and were often at the center of a town. “Cathedra” is the Greek word for chair, so that means that Cathedrals were the chair of authority for a bishop.
Cathedrals often took centuries to build. Some people could work on one cathedral and still never see it completed. Romanesque, a type of style made in the 12th century, was the kind of cathedral that was the most common style in history.
These types of cathedrals have pointed arches, flying buttresses, and very high ceilings. All cathedrals are made in the shape of a cross and are pointed west to east. Flying buttresses are pillars that support the high ceilings. Gargoyles are stone beasts that are sometimes added to the flying buttresses.
It takes lots of money to build a cathedral, so the church sold indulgences. They said if you bought an indulgence, your sins would be forgiven.