As of 2026-10-12, Bananal Island tops the list with 350 km.
- #1 Bananal Island — 350 km
island in Tocantins, Brazil
Bananal Island is a large river island formed from the bisection of the Araguaia River, in southwestern Tocantins, Brazil. The island is formed by a fork in a very flat section of the Araguaia; the western stream of the fork retains the name Araguaia and the eastern one is called the Javaés River. By reuniting later, both streams form Bananal Island, which is the second largest river island in the world and the largest without an ocean coastline, at 320 kilometres (200 mi) long and 55... Read more on Wikipedia.
Wikidata - #2 Ilha Grande do Gurupá — 129 km
river island
Ilha Grande de Gurupá is a large river island of the Amazon River delta. It lies in the Brazilian state of Pará, west of Marajó and near the confluence of the Amazon and the Xingu. The island has an area of 4,864 square kilometres (1,878 sq mi). Read more on Wikipedia.
Wikidata - #3 Balta Ialomiţei — 94,000 m
Balta Ialomiței is an island on the Danube, located in Ialomița County and Călărași County, Romania. It is surrounded by two branches of the Danube, Borcea and Dunărea Veche. The island has an area of 831.3 km2 (321.0 sq mi), with a length of 94 km (58 mi) and a width of 5 to 12.5 kilometres. The average height is 10 to 17 metres. Read more on Wikipedia.
Wikidata - #4 Margarita Island — 90,000 m
island in the Magdalena River, Colombia
Margarita Island, also called Mompox Island, is an inland river island in the Magdalena River, near Mompos town of interior Colombia. It is located in the Bolivar Department, on the border with the Magdalena Department in northern Colombia. With an area of 2100 to 2200 km2, it is the largest island in Colombia and the fourth largest river island in the world after the islands of Marajo, Bananal and Tupinambarana. It had a population of 117,210 in 2008. Read more on Wikipedia.
Wikidata - #5 Great Brăila Island — 60,000 m
Romanian Island on the river Danube
The Great Brăila Island is an island on the Danube river in the Brăila County, Romania. It has on average 57.9 km (36.0 mi) length and 18.6 km (11.6 mi) width, with a total area of 710 km2 (270 sq mi). The two river branches which separate it from the mainland are Măcin Branch and Vâlciu Branch. Read more on Wikipedia.
Wikidata - #6 Biffeche — 56,000 m
former country
Biffeche or Bifeche is an area of Senegal centred on the town of Savoigne, around 30 kilometres north-east of the major coastal city of Saint-Louis. Read more on Wikipedia.
Wikidata - #7 Majuli — 54,800 m
island in Assam, Northeast India
Majuli is the largest river island in Assam, a state in Northeast India. It is bordered by the Brahmaputra River to the south and east, the Subansiri River to the west, and an anabranch of the Brahmaputra to the north. Read more on Wikipedia.
Wikidata - #8 Island of Montreal — 50,000 m
island in the St. Lawrence River, site of the city of Montreal, Quebec
The Island of Montreal is an island in southwestern Quebec, Canada, which is the site of a number of municipalities, including most of the city of Montreal, and is the most populous island in Canada as well as the world's most populous freshwater island. It is the main island of the Hochelaga Archipelago at the confluence of the Saint Lawrence and Ottawa rivers. Read more on Wikipedia.
Wikidata - #9 Csepel Island — 48,000 m
island
Csepel Island is an island in the Danube in Hungary. It is 48 km (30 mi) long, with a width generally ranging from 5 to 8 km. It has an area of 257 km2 (99 sq mi) and its population is 165,000. The island extends south from Budapest, and its northern section forms the city's District XXI. Most of the island is accessible from Budapest by HÉV suburban railway, and the northern part belongs to the metropolitan area of the capital. Towns include Ráckeve, Szigetszentmiklós, Szigethalom,... Read more on Wikipedia.
Wikidata - #10 Szentendre Island — 38,000 m
island
Szentendre Island is an island in the Danube River between the Danube Bend and Budapest in Hungary. The island is flanked by the Szentendre branch of the Danube to the west, and the main branch of the river to the east. It is 31 km long with an area of 56 km2, and forms part of the Szentendre District of Pest County. Read more on Wikipedia.
Wikidata