## 3 Case Study  
The survey sample is represented by the people whose place of work is located in the provinces of Turin, Trento, Bologna, and Rome. The reasons for the selection of these four particular provinces are due to their distinct peculiarities, both physical and historical-urban, with reasonable hypotheses of different impacts on urban circulation, and to the high number of responses to the survey 59% of the data are from workers from the four cities, specifically 18.7% from Bologna, 12.2% from Rome, 12.4% from Trento, and 15.6% from Turin)  
Rome is the biggest city in Italy, both in terms of population, with 2.8 million inhabitants (the double of the second, Milan), and surface, with almost 1300 square km (again the double of the second, Ravenna). Its density is around 2150 inhabitants/km\({}^{2}\). Rome is also the eighth-largest city in Europe in terms of population, just below Madrid andKyiv and above Bucharest and Paris. Rome shows a very important level of congestion, especially on the ring roads and consular radial roads. Daily commuting in Rome is influenced by the concentration of work opportunities in certain areas of the city. Rome is in fact characterised by a medium-low degree of spatial decentralisation of functions in the city [50]. It is estimated that the number of people not resident in the city of Rome who travel daily exclusively for work and study is 420,000 [51]. A large percentage comes from other cities in Regione Lazio and Regione Campania. The road system is characterised by a radial structure [52], with a relevant role played by the ancient Roman consular roads, an uneven degree of accessibility of public transport that tends to degrade from the centre towards the periphery [53], and the dominance of road transport [54]. According to the TomTom index, Rome is the second-most congested city in Italy, with an estimated annual time loss of 82 h per driver [55]. Moreover, important differences exist in the quality of the urban space when comparing the city center, which is very attractive for tourists and is the seat of many offices of public and private companies, with the suburban residential areas. The motorization rate in Rome in 2020 was 645 cars per 1000 inhabitants [56], the fourth highest among large Italian cities. Turin is the fourth-biggest city in Italy, with 850,000 inhabitants, comparable to other European cities like Amsterdam, Marseille, Krakow, and Valencia. Turin is also in the top list for population density in Italy (considering cities with more than 50,000 inhabitants) with around 6525 inhabitants/km\({}^{2}\). The motorization rate in Turin in 2020 was 655 cars per 1000 inhabitants [56], an average level for large Italian cities. The city is much relying on private car use, which has been historically prioritized over public transport or active mobility. Bologna is the seventh-biggest city in Italy, with 390,000 inhabitants, comparable to Tallinn, Iasi, Sintra, or Brno. Its population density reaches 2780 inhabitants/km\({}^{2}\). The motorization rate in Bologna in 2020 was 614 cars per 1000 inhabitants [56], well below the average level for large Italian cities. Bologna will be the first city in Italy to have a speed limit of 30 km/h in almost all the roads within its municipality by June 2023 (with only some large roads allowed up to 50 km/h) [57]. The city is also well known for its high number of bicycle usage, especially within the historical city centre. Trento is the smallest of the four cities that we analyzed, with around 120,000 inhabitants, and also the one with the lowest population density, 750 inhabitants/km\({}^{2}\). The official motorization rate in Trento in 2021 was 3.9 cars per inhabitant [56], but this figure is caused by the very high number of rental car registrations, due to favorable fiscal conditions compared to other Italian cities [58].