On July 3 Polish-Lithuanian forces started moving towards the enemy. On July 8 the the huge army crossed the borders, with the intention of marching against Malbork. But Grand Master Ulrich von Jungingen tried to trap the enemy. He knew from his own spies where the enemy would cross the Drweca river, and positioned his forces on the opposite side of the river near the small village of Drweca. The river crossings were fortified with stockades and the castles nearby reinforced. But the Jagiello and Vytautas did not want to fight in the area where the Teutonic Knights would have an advantage and decided to approach Malbork from the other direction, via the town of Dabrowno. To head them off the Teutonic Knights took another route. Their intention was to oppose the huge enemy army in Grunwald, Frygnowo, or in Rychnowo.
On July 13 the Polish-Lithuanians reached the town of Dabrowno, occupied by the Teutonic Knights, and now populated by German citizens. Within a few hours the Poles and Lithuanians captured it. The town was burned to the ground in the full knowledge that this would be seen by Teutonic Knights who were just kilometres away. The fire and heavy smoke was indeed seen that night by the Grand Master and his army. The Polish-Lithuanian army left Dabrowno before dark on 15 July, and by sunrise they had reached Lake Lubien. This time the Grand Master found the army of Jagiello and Vytautas, and for second time planned to oppose the enemy, on Tuesday 15 July, at the villages of Grunwald, Stebark and Lodwigowo near Lake Lubien.
