Polish–Lithuanian Neutral Strip was a demilitarised zone between Lithuania and Republic of Central Lithuania, and later Poland, that was established on 17 December 1920, following the treaty of Kaunas and disestablished on 22 May 1923. It was established by the League of Nations, to stop countries from fighting, following the Central Lithuanian Offensive on Kaunas. The zone was located on the borders of the separated countries between towns of Pabradė and Valkininkai and was, on average, 6 km wide on each side of the border.