the engines against the Walls

After having resisted for centuries, the Walls were in danger of being overturned in the 20th century. The threat came not from foreign armies but from cars.
They were used as a racetrack for speed races and rallies. This was the case for the first part of the century when car ownership was reserved for wealthy families.
Things changed when from the end of the 1950s, encouraged by the Fiat small cars, the car market attracted a large mass of the population. For the Walls, the car boom meant their use as a ring road for all kinds of cars, from tiny 500s to bulky buses.

The Walls and the Spalti were then transformed into an immense car park. This condition worsened from year to year and lasted until the second half of the 1980s when, urged on by the Monuments Superintendency, the Municipal Administration implemented the first measures that freed the Walls from the presence of cars.

Resistance of various kinds opposed those measures but did not stop the direction taken by the Municipal Administration that saved the integrity of the City Walls and the "Spalti" and returned an immense urban park to the city.