In the cemetery in Karviná-Doly there is a grave of Wenceslas Olszak (1868-1939) a Polish doctor, national and social activist in Těšín Silesia. Between 1918 and 1920 W. Olszak was a member of the National Council of the Duchy of Těšín, and between 1929 and 1936 he was the first Pole to hold the office of mayor of Karviná. From 1935 he headed the Supreme Council of Poles in Czechoslovakia. He was arrested as early as 2 September 1939, then released. On 7 September he was severely beaten by the Gestapo and German mine officials, and died of his injuries on 11 September 1939. His wife Maria (1883-1951) and son Antoni (1907-1926) are also buried in the grave. The grave is under the care of the Polish Medical Association in the Czech Republic.