Tourism destinations are often confronted with the challenge of balancing the capacity of their transport systems, between peak and off-peak periods. In order to properly design, implement and measure solutions’ impacts, data on mobility demand are required. This paper presents an integrated mobility data monitoring scheme, tested for the first time in Rethymno and Platanias, two small insular cities in Crete. The monitoring scheme included mobility and environmental indicators measurements, field research and data analysis methods. Results helped to capture the variation in traffic flows and driving behaviours by vehicle type and daytime, between winter and summer, and better understand the city’s seasonal mobility characteristics. Cities of similar typology (Mediterranean climate, seasonal flows, linear coastal development, limited transport network capacity) can benefit from such simplified schemes. Since the cost is low, cities can acquire real-time data to feed smart tools, like GIS models. Data interpretation allows policymakers, governmental authorities and tourism stakeholders to design traffic calming measures in high-risk locations, to enhance traffic safety for citizens and visitors and improve conditions for active mobility, as well as to introduce policy measures and behaviour change activities for drivers. Cross-analysis with tourism and user behaviour data supports overall mobility and resilience planning.