International audienceThe Canada-France Imaging Survey (CFIS) will map the northern high Galactic latitude sky in the uband ("CFIS-u", 10,000 deg 2) and in the r-band ("CFIS-r", 5,000 deg 2), enabling a host of stand-alone science investigations, and providing some of the ground-based data necessary for photometric redshift determination for the Euclid mission. In this first contribution we present the u-band component of the survey, describe the observational strategy, and discuss some first highlight results, based on approximately one third of the final area. We show that the Galactic anticenter structure is distributed continuously along the line of sight, out to beyond 20 kpc, and possesses a metallicity distribution that is essentiall...