The Stelmužė Oak is a common oak tree which grows in the former Stelmužė Manor park by Stelmužė [stεɫˈmʊʒeː] village, Zarasai district, Lithuania. The oak measures 3.5 m in diameter and 13 m in girth at its widest part; being 2.8 m. and 9.58 m at waist level.