conservation

Top 10 Largest Ramsar Wetlands by Area in the World

The ten biggest Wetlands of International Importance under the Ramsar Convention, ranked by designated site area, from Brazil's 12-million-hectare Rio Negro to Mali's Inner Niger Delta.

Updated October 20, 2026 10 ranked 3 sources

Quick answer

Rio Negro in Brazil is the largest Ramsar Site, with a designated area of 12,001,614 ha (about 120,000 km2). Ngiri-Tumba-Maindombe in the DR Congo is second at 6,569,624 ha and Queen Maud Gulf in Canada third at 6,278,200 ha, per the per-site areas compiled from the Ramsar List.

The Ramsar Convention is the global treaty for wetland conservation. Countries that join it designate Wetlands of International Importance, known as Ramsar Sites; as of March 2026 there were 2,526 of them covering 253,150,727 hectares. Most Ramsar Sites are small marshes, lagoons and estuaries, but a handful are vast river basins, floodplains and swamp forests. This list ranks the ten largest single sites by their designated area. Eight of the ten are in Africa.

Designated area (ha)

Designated area (ha)
Rio Negro
12001614 ha
Ngiri-Tumba-Maindombe
6569624 ha
Queen Maud Gulf
6278200 ha
Grands affluents
5908074 ha
Sudd
5700000 ha
Okavango Delta System
5537400 ha
Lisima Lya Mwono
5367000 ha
Plaines d'inondation des Bahr Aouk et Salamat
4922000 ha
Bassin de la Lufira
4470993 ha
Delta Interieur du Niger
4119500 ha

The ranking

1

Rio Negro

The largest Ramsar Site by a wide margin, covering 12,001,614 ha of the Rio Negro in the Brazilian Amazon - nearly twice the area of the next site.

Country: BrazilArea (ha): 12,001,614
2

Ngiri-Tumba-Maindombe

A 6,569,624 ha complex of flooded forest, rivers and lakes in the Democratic Republic of the Congo.

Country: DR CongoArea (ha): 6,569,624
3

Queen Maud Gulf

An Arctic coastal lowland in Nunavut covering 6,278,200 ha, the largest Ramsar Site in North America.

Country: CanadaArea (ha): 6,278,200
4

Grands affluents

The Republic of the Congo's largest Ramsar Site, covering 5,908,074 ha of the Congo River's large tributaries.

Country: Republic of the CongoArea (ha): 5,908,074
5

Sudd

The vast swamp where the White Nile spreads out across South Sudan; the Ramsar Site covers 5,700,000 ha.

Country: South SudanArea (ha): 5,700,000
6

Okavango Delta System

A 5,537,400 ha inland delta in Botswana where the Okavango River fans out into the Kalahari.

Country: BotswanaArea (ha): 5,537,400
7

Lisima Lya Mwono

Angola's highland source wetlands of the Okavango system, listed at 5,367,000 ha.

Country: AngolaArea (ha): 5,367,000
8

Plaines d'inondation des Bahr Aouk et Salamat

The floodplains of the Bahr Aouk and Bahr Salamat rivers in Chad, covering 4,922,000 ha - Chad's largest Ramsar Site.

Country: ChadArea (ha): 4,922,000
9

Bassin de la Lufira

The Lufira River basin in the south of the DR Congo, covering 4,470,993 ha - the country's second site in this top 10.

Country: DR CongoArea (ha): 4,470,993
10

Delta Interieur du Niger

Mali's Inner Niger Delta, where the Niger River floods a huge inland plain each year; the Ramsar Site covers 4,119,500 ha.

Country: MaliArea (ha): 4,119,500

Full comparison

# Name CountryArea (ha)
1 Rio Negro Brazil12,001,614
2 Ngiri-Tumba-Maindombe DR Congo6,569,624
3 Queen Maud Gulf Canada6,278,200
4 Grands affluents Republic of the Congo5,908,074
5 Sudd South Sudan5,700,000
6 Okavango Delta System Botswana5,537,400
7 Lisima Lya Mwono Angola5,367,000
8 Plaines d'inondation des Bahr Aouk et Salamat Chad4,922,000
9 Bassin de la Lufira DR Congo4,470,993
10 Delta Interieur du Niger Mali4,119,500

How we ranked this

Sites are ranked by the designated area of each individual Ramsar Site, in hectares, largest first. All ten areas come from one table: the per-site areas in Wikipedia's List of Ramsar Sites (revision of 2 September 2026), which is compiled from the Ramsar Sites Information Service. Only single designated sites count: Bolivia's 2013 Llanos de Moxos designation, often reported as about 6.9 million ha, was made as three separate Ramsar Sites (Rio Yata 2,813,229 ha, Rio Blanco 2,404,915 ha and Rio Matos 1,729,788 ha), none large enough for the top 10. Natural wetland extent does not count, so the Pantanal, split across several smaller sites, does not appear. Ramsar Sites can be extended or redrawn; this ranking reflects that table as of September 2026.

FAQ

What is the largest Ramsar Site in the world?

Rio Negro in Brazil, with a designated area of 12,001,614 ha (about 120,000 km2), nearly twice the area of the second-largest site, Ngiri-Tumba-Maindombe in the DR Congo.

Why isn't Llanos de Moxos on this list?

Bolivia's 2013 Llanos de Moxos designation, reported as about 6.9 million ha, was made as three separate Ramsar Sites: Rio Yata (2,813,229 ha), Rio Blanco (2,404,915 ha) and Rio Matos (1,729,788 ha). This list ranks single sites, and none of the three is large enough for the top 10.

Why isn't the Pantanal on this list?

This list ranks designated Ramsar boundaries, not natural wetland extent. The Pantanal is covered by several separate Ramsar Sites; the largest, Pantanal Boliviano, is 3,189,888 ha, below the top 10.

Sources