Sanctuary of the Madonna di San Luca

The Sanctuary of the Madonna of San Luca is a basilica church in Bologna, northern Italy, sited atop a forested hill, Colle or Monte della Guardia, some 300 metres above the city plain, just south-west of the historical centre of the city.While a road now leads up to the sanctuary, it is also possible to reach it along a 3.8 km monumental roofed arcade consisting of 666 arches, which was built in 1674–1793. It was meant to protect the icon as it was paraded up the hill. A yearly procession from the Cathedral of San Pietro in the centre of Bologna to the Sanctuary goes along this path. Originally the arches held icons or chapels erected by the patron family.

Source: Wikipedia