In Portugal, the Tagus estuary, the largest and most important wetland for this group of birds, is the starting point for the documentary “Long-Distance Migrants – Between the Tagus and the Arctic”, with images never before broadcast on TV. Flocks of 40 to 50 thousand birds, nocturnal captures and individual marking of these birds were recorded in the two years of shooting this work, which also followed the birds (and researchers) to Iceland, capturing the birth of the offspring, and the threats that these face and that Portuguese, Icelandic and English researchers are trying to unravel. Back in the Tagus estuary, local threats, namely the intention to operate a commercial airport on the Montijo peninsula, the geographic heart of this wetland, are also addressed. This international documentary, recorded between 2018 and 2020, presents migratory birds like never before: a natural spectacle shared by the various countries that have the privilege of receiving them and that everyone is responsible for preserving!