A town in the flooded grassland, on a river
With what grows here (rice, pulses), this land can feed a town of about 120,000 people from farms less than a day's cart from its walls, about the size of Venice around 1300.
Build a town in the flooded grassland, on a river
A town of 10,000 here
Its grain comes from 7 km around, 0.5 days by cart (comfortable). About 280 villages and 79,000 country people farm it, and the town keeps about 40 scholars. Grown to 40,000 people, its grain comes from 14 km around, 1 day by cart (comfortable). Grown to 150,000 people, its grain comes from 28 km around, 1.5 days by cart (strained). Grown to 1,000,000 people, its grain comes from 72 km around, 3 days by cart (fragile).
In history
On the inland delta of the Niger in Mali, people settled for good at Djenné-Djeno around 250 BC, after a dry spell shrank the swamps. They grew African rice in the flood and ate catfish, Nile perch and above all beef; dunes close by gave the cattle somewhere to go when the water rose, and ground for millet. By about AD 800 the town and its surroundings may have held 10,000 to 27,000 people, behind a mud-brick wall almost two kilometres around. Its rice is believed to have gone to other centres, Timbuktu among them, and was probably traded for Saharan salt, copper and dried fish; glass beads from as early as the third century BC show how far its trade reached.
Where the Tigris and Euphrates spread into the marshes of southern Iraq, the Marsh Arabs lived in arched reed houses, on the bank or on islands built up from reeds and mud. Some families herded water buffalo; others grew rice in small plots cleared in April and sown in mid-May, reading the seasons from the rising of the Pleiades and Sirius. Each sheikh kept a mudhif, a great reed guest-house where disputes were settled and visitors received. The marshes were also a refuge: escaped slaves and serfs hid there during the Zanj Rebellion.
How large a city?
| People | Grain from | By cart | Villages | Scholars | By ship to fit in a day |
|---|---|---|---|---|---|
| 3,000 | 4 km around | 0.5 days (comfortable) | 83 | 12 | – |
| 10,000 | 7 km around | 0.5 days (comfortable) | 280 | 40 | – |
| 40,000 | 14 km around | 1 day (comfortable) | 1,100 | 160 | – |
| 150,000 | 28 km around | 1.5 days (strained) | 4,200 | 600 | 20% |
| 1,000,000 | 72 km around | 3 days (fragile) | 28,000 | 4,000 | 90% |
Living there
There are no woods to spare here. The town needs about 6,200 tonnes of wood a year for its hearths and workshops: it burns straw (about 8,000 tonnes a year), dung and brush, and buys the rest. Provisional figure.
Its market sells grain, rice, flax, cotton and sugar cane, and buys timber, iron and salt. About 7 market towns stand in its countryside.
About 20% of what its people eat does not come from the fields. Of that share: herds 23%, fish 35%, gardens 42%. That is some 1,000 livestock units on 15 km² of pasture, and about 340 fishers in 85 boats. Hearth estimate.
What makes it hard
- The flood never comes the same way twice. A town that lives on flood rice must plan for the year the water stays low and the year it drowns the fields.
- When the river rises, the herds must leave for higher ground, and someone has to go with them and come back.
- Malaria and schistosomiasis are endemic in the marsh: a town here always has its sick.
- Reed is cheap and quick to build with, but a great reed hall must be rebuilt about every ten years: a town of reed always has a building going up somewhere.
- A marsh hides people. Runaway slaves and rebels have long vanished into the reeds, out of a ruler's reach.
Hard years
About one year in 8, the harvest falls below four fifths of a normal one: the town is short of some 660 of the 2,300 tonnes of grain its land gives it, and the water lets it bring the gap in. A plague that kills 39% of the town, as the Black Death did in Europe's towns, would leave about 200 km² of its fields idle.
What it can make
Grain, Rice, Flax, Cotton, Sugar cane, Dye plants, Orchards, Herbs, Potato, Maize, Wool (at a cost), Horses (at a cost), Cattle and hides, Cheese, Pigs and bacon (at a cost), Goats, Honey and wax, Silk, Fish, Shipyards (at a cost)
What its land cannot give, a town here must buy: timber.
What it lives on
Underground
What a city digs depends on the rock under it: Granite, Volcanic rock, Ultramafic rock (peridotite, serpentinite), Schist and gneiss, Marble, Limestone and chalk, Sandstone, shale and clay, Salt beds, River gravels and sands
Found here
Gathered (Rerum): African Wild Rice, Wild Rice Straw, American Alligator Meat, Antelope Grass Grain, Beetle Wing, Bourgou Seeds, Bourgou Stem, Buriti Fibre
Hear it
- The town: Fantasy Medieval City (album RPG Ambiences Vol. 6)
- The market: Medieval Village Marketplace (on Patreon, Guardian tier)
- The quays: Medieval Harbor District (on Patreon, Guardian tier)
- The countryside: Farmyard with People and Animals (on Patreon, Guardian tier)
Flooded Grassland in Biomes: plants, animals, hazards and sounds
The same climate
A town in the flooded grassland, A town in the flooded grassland, on the coast
By city size
1,000, 3,000, 10,000, 30,000, 100,000, 300,000, 1,000,000
Sources
- Wikipedia contributors, Djenné-Djenno, Wikipedia, 2026. en.wikipedia.org
- Wikipedia contributors, Marsh Arabs, Wikipedia, 2026. en.wikipedia.org
- Wikipedia contributors, Mudhif, Wikipedia, 2026. en.wikipedia.org
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