"Above the Bzura River without Change" is the only permanent exhibition in Poland devoted to the positional fighting of World War I in western Mazovia. The stylised elements of the trenches, the unique graphic design, and the numerous exhibits from the battlefields allow visitors to travel back in time and trace the dramatic events of the frontline, when more than 500,000 people fought in the trenches against each other: winter attacks by the infantry, heavy artillery fire, murderous shelling by machine guns and mortars, and wave after wave of chlorine attacks.