In order to limit the results of searches to meaningful groups,
priority is graded by a combination of a building's contribution to the evolution of Gothic architecture as well as size.
There are four groups.
As you would expect the great cathedrals and abbeys with the most complexity form the first,
large buildings that are not too complex form the second,
and the third are all the others that have some carved or decorative work that makes them more interesting for the historian.
The remainder that are simpler in detail if not in scale, form the fourth group
There are about 1,550 churches in the Paris Basin that contain something from this period.
Tick the outliers box to include all those beyond the boundaries of the Paris Basin, which is the calcaire geological foundation of northern France.
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