It was built by the Countess Matilde of Canossa and stands on the eastern
side of Piazza delle Erbe, a little below the square level.
It dates back to the end of the 11th century and has a circular plan. Externally it is
characterised by thin and jutting pilaster strips linked above by a crown of hanging small
arches.
The interior, realized with very simple structures and bare walls, gives an impression of
very deep spiritual concentration. The interior circular plan is characterized by a first
circle of columns supporting the voults and by a second circle on the upper floor, thus
creating light and shade effects.
The Rotonda is very similar to the church of San Tomè di Almenno in the province of
Bergamo.
Next to the "Rotonda di San Lorenzo" there is the "Clock Tower"
recently restored to new splendour.
