This document summarizes big transport data collection and analysis efforts in Thessaloniki, Greece. Over 1.4 million people live in Thessaloniki and make an estimated 1.3 million daily trips using private vehicles, public transit, taxis, bicycles, and other modes. Sensors including Bluetooth detectors and GPS data from 1,200 taxis and 600 buses provide real-time and historical data on traffic flows, speeds, travel times, origins and destinations, and mobility patterns. This data is analyzed at the Center for Research and Technology Hellas to support improved transportation planning, modeling, and driver information systems.