This aim of this article is to analyse the role of cartography in operation activities during the Great Northern War. So far, only Swedish materials from that period have been studied, and this work concerns two maps made for the needs of the Russian army. Both relics were made by the general-engineer Joseph-Gaspar Lambert de Guerin (in Russian: Жозеф Гаспар Ламбер де Герен). They were produced within the first three months of 1706 for the needs of the so-called Campaign of Grodno. Cartographic materials show that preliminary terrain survey by engineers was already used in the Russian army at the time. In the first stage, the officers developed the marching routes from Grodno to Tykocin (only one of such maps has been preserved: Carte d’une partie de la Lithuanie et de la Pologne). At least four of such routes were surveyed; three places were also found where the Neman river could be crossed, as well as fords and bridges that allowed the army to cross over the Biebrza river. Then, in the second stage, as the whole army had to flee from the Swedish troops, all the routes were combined on one map: Environsde Grodno et Ticochin. The text presents the mistakes made by Lambert when producing this map. Despite its imperfections, the cartographic documentation contributed to the successful escape of the Russian forces from Grodno (22.03 / 2.04). After reaching Tykocin, Peter I’s troops successfully crossed over the Narew river (29.03 / 9.04), and then went toward Brest Litovsk (4/15.04). The estimated average daily marching speed was 18.9 km, but within the two record days, the army managed to walk almost 70 km.