The ancient fortified town of Zrnovo was located atop the Avala mountain in 12th-15th century. In 1922 the citizens of nearby villages have built a stone monument over the tomb of an unknown Serbian soldier who was killed by Austro-Hungarian howitzer in 1915, during the World War I. More than a decade later, by an order from King Alexander Karadjordjevic, the leftovers of Zrnovo were demolished to free the space for the new monument. When the new memorial complex was finished in 1938, the coffin with the remains of the unknown soldier was moved to the crypt inside the new monument.
The monument is used for the official commemorations of the important historic dates between 1912 and 1918.
The monument was designed by famous sculptor Ivan Mestrovic. It was declared Monument of Culture of Exceptional Importance in 1987, and it is protected by Republic of Serbia.