Little War Island or Malo ratno ostrvo (Serbian Cyrillic: Мало ратно острво) or Horse Island or Konjsko ostrvo (Serbian Cyrillic: Коњско острво) is a river island (ada) in Serbia, located at the mouth of the Sava river into the Danube. It is part of the Belgrade City proper, the capital of Serbia, and belongs to the municipality of Zemun.
The island is located between the southern bank of the Great War Island and the right bank of the Danube in the municipality of Novi Beograd (the neighborhood of Ušće), just 200 metres (660 ft) away from the Sava's confluence into the Danube.
The island used to be significantly larger before the World War II. When construction of Novi Beograd began in 1948, the sand from the island was transported to the mainland by large conveyor belts and used for covering the swamp on which the new city was to be built. In the process, the island shrank, and sometimes it is poetically said today that "Novi Beograd is a city on the island".
What's left of the island is basically a thin strip of land, less than 300 metres (980 ft) long and 60 metres (200 ft) wide. The island is completely covered by vegetation (poplar trees) and inaccessible for visitors, but can be nicely observed from the barges-restaurants on the Danube's bank.
Coordinates: 44°49′24.32″N 20°26′16.21″E / 44.8234222°N 20.4378361°E