GSW - Main Warmian Trail - is a project focusing on the longest section of the Copernicus Trail (370 km long) crossing the areas of historic Warmia. The trail runs through picturesque towns with numerous cultural monuments and beautiful nature reserves and is marked along its entire length. The route runs primarily through the places where Nicolaus Copernicus lived and worked. It begins in Olsztyn, then leads through Dobre Miasto, Lidzbark Warmiński, Pieniężno, Braniewo, Frombork, Elbląg, from where it heads towards Kępki, the place where the next Pomeranian section of the trail with a length of 118 km begins. The end of the Pomeranian section is located in Gardea. From there, the trail enters the Kuyavian-Pomeranian Voivodeship and reaches Grudziądz.
The Warmian section of the trail - named GSW - is 237 km long and is great for long-distance running in the FKT formula, as well as any other formula to complete it on foot.
This route overlaps with the Olsztyn - Pieniężno route, but is more than twice as long.