The Yugoslav monitor Drava was a river monitor operated by the Royal Yugoslav Navy between 1921 and 1941. She was originally built for the Austro-Hungarian Navy as the name ship of the Enns-class river monitors. As SMS Enns, she was part of the Danube Flotilla during World War I, and fought against the Serbian and Romanian armies from Belgrade to the lower Danube. In October 1915, she was covering an amphibious assault on Belgrade when she was holed below the waterline by a direct hit, and had to be towed to Budapest for repairs. After brief service with the Hungarian People's Republic at the end of the war, she was transferred to the newly created Kingdom of Serbs, Croats and Slovenes, and renamed Drava. She remained in service throughout the interwar period, but was not always in full commission due to budget restrictions.
View from the Belgrade Fortress over Grosser Krieg Island. Enns was supporting the October 1915 crossings of the Danube near the island when she received a direct hit and was put out of action
Ju 87 Stuka dive bombers of Sturzkampfgeschwader 77 sank Drava near Čib on the morning of 12 April 1941
River monitors are military craft designed to patrol rivers.
Model of USS Monitor
The Civil War era river monitor Neosho
A Mobile Riverine Force monitor using napalm in the Vietnam War
The river monitor Sava (formerly Bodrog) fired the first shots of World War I. She is now a floating museum anchored along the Sava river in Belgrade, Serbia