octagonal

Later, the square tower was crowned with an octagonal turret, sometimes with a conical roof, as in Cremona and Modena cathedrals.

The angles are emphasized by octagonal projections, the panelling of which seems to have ruled that of the whole structure.

In the 16th century an octagonal lantern in two strings crowned with a conical roof was added.

An octagonal tower of two storeys rises above the corbelled eaves.