Von Thünen Model:
Rural land-use sandbox

Von Thünen’s “isolated state”: one city on a flat, featureless plain. Every farmer must haul what they grow to that one market, and every kilometre costs money. Change the numbers and watch the countryside sort itself into rings.

Market gardens & dairy

Forestry (timber & firewood)

Grain

Ranching & livestock

Not worth farming

Dashed line A–A′ is the slice shown in the chart below 160 × 160 km plain · 20 km grid

Bid-rent along A–A′

what a farmer can pay for land, by distance

Scenarios

Starting point: an 1826 farm cart on a dirt road.

Getting to market

Transport cost is the engine of the model. Every crop pays it, but the perishable and the bulky pay most.

Transport cost 1.00× cart 1.00 = an 1826 horse cart. Below 1: railways, trucks, refrigerated shipping. Above 1: bad roads.

Where is the market?

Navigable river through the market

Barges cost a quarter of a cart per kilometre.

A rival town 44 km to the east

Same prices, same crops. Farmers sell to whichever town is cheaper to reach.

The crops

Perishability is how fast a crop’s value drains away with every kilometre hauled. Bulky, heavy goods like timber behave the same way.

Ring widths

km from the market, along A–A′

Land use	From	To	Width

How the model decides

Every crop makes a bid for each patch of land: the most it could pay in rent and still make money. The bid is highest at the market gate and falls with every kilometre of hauling. Perishable and bulky products fall fastest, so they can only outbid other crops close to town. Whichever crop bids highest gets the land — and because bids fall in straight lines at different slopes, the winners come out in bands. On a flat plain with one market, bands are rings.

The chart under the map is a slice through the map along the dashed line. Where two curves cross, a ring boundary sits directly above it. Where the last curve reaches zero, farming stops.

Von Thünen only got clean rings by assuming a lot away. Each assumption is a place where the real world bends the pattern — and each one is something this sandbox lets you break.

One market An isolated city with no competitors. Break it: add the rival town.
Flat, uniform land Equal soil, climate and terrain everywhere. Break it: not modelled here — think about a mountain or a fertile valley.
One kind of transport Every direction costs the same per kilometre. Break it: add the river.
Farmers maximise profit They grow whatever pays best at their distance. Kept as-is.

Try this

1. Halve the transport cost. What happens to the outer edge of farming?

Every ring stretches outward. The order of the rings does not change — only how far each one reaches. This is what railways did in the 1800s: a city’s food supply suddenly came from hundreds of kilometres away.

2. Drop dairy’s perishability to 0.40, as if refrigeration had been invented. Which ring vanishes, and why?

Forestry disappears. Dairy no longer loses value fast, so its bid stays above forestry’s at every distance. A ring only exists where a crop wins somewhere; a technology that flattens one crop’s curve can erase its neighbour.

3. Turn on the river. Describe the new shape in one sentence.

The rings stretch out along the river, because it is cost of transport, not straight-line distance, that decides land use. A farm far upriver can be “closer” to market than a farm a short way overland.

4. Put the market on the coast. What happened to the rings?

They became half-rings. Half the hinterland is sea, so the land the city can draw on is fan-shaped. Real port cities look like this.

5. Add the rival town. Where do the two towns’ hinterlands meet, and what happens there when you cut transport cost?

A dividing line appears halfway between the towns; farmers on each side sell to their nearer market. With cheap transport the outer rings would overlap, but each farmer still picks the closer town, so the boundary stays and the rings on both sides are cut flat against it.