The natural monument is the protected walnut tree (Juglans regia L). It is located in Nova Topola, Gradiška, in the northern part of the Republic of Srpska. The tree has a girth of 637 centimeters and is 34 meters high according to data from 2003, making it one of the tallest trees in the Republic of Srpska.
The tree is estimated to be over 300 years old!
Source: Wikipedia