Study Reveals Dirt Trails Could Help Cities Design Better Pedestrian Networks

Why do people ignore sidewalks and cut across grass even when proper walkways already exist? A new Hungarian study suggests the answer is surprisingly simple: humans naturally try to save energy while walking.

Researchers from the University of Debrecen and the Budapest University of Technology and Economics have found that the informal dirt trails often seen in parks and residential areas are not random acts of laziness or impatience. Instead, they may be the result of subconscious decisions made by pedestrians seeking the easiest and least physically demanding route.

Their findings, published in the journal Cities, could change the way urban planners design sidewalks, parks and public spaces in the future.

People Do Not Always Choose the Shortest Route

The researchers argue that pedestrians do not necessarily look for the shortest geometric path. Instead, they instinctively choose routes that require the least physical effort.

Previous scientific studies have shown that walking on grass, gravel or uneven ground uses more energy than walking on smooth pavement. Humans naturally adjust their movement to reduce fatigue, even without realising it.

This means a person may sometimes walk a slightly longer route if it feels easier overall. In other cases, they may cut directly across a lawn if that saves enough time and energy to make the effort worthwhile.

The study says these repeated decisions slowly create “desire paths”, the narrow dirt trails formed by constant foot traffic across green spaces.

A Computer Model That Predicts Human Walking

To test their theory, the researchers created a computer model that simulates how pedestrians move through parks and urban spaces.

The model divided public areas into thousands of tiny sections connected through possible walking routes. Different surfaces, such as pavement, grass, gravel and roads, were given different “cost factors” based on how difficult they are to walk across.

For example, grass was treated as more physically demanding than pavement. Roads and parking areas were given even higher penalties because pedestrians see them as unsafe or uncomfortable.

Using this information, the system calculated the routes requiring the least total energy. The results were then compared with real-world pedestrian trails.

The outcome closely matched reality.

Real Parks in Hungary Confirmed the Theory

The researchers tested the model in two Hungarian cities, Debrecen and Budapest.

In Debrecen, they studied a residential square where pedestrians had already created a network of shortcuts between apartment buildings, bus stops and crossings. The computer model successfully reproduced most of the existing trails with remarkable accuracy.

The same happened in Budapest’s Florian Square, where diagonal dirt paths cut through lawns and green areas. The simulations predicted where people would leave formal sidewalks and where they would stay on paved routes.

One important finding was that pedestrians are willing to make small detours if it reduces effort. Another was that existing dirt trails attract even more people over time because they become easier to walk on than untouched grass.

This creates a cycle where small shortcuts gradually grow into permanent informal pathways.

What This Could Mean for Future Cities

The study suggests that desire paths should not simply be viewed as signs of poor behaviour or failed landscaping. Instead, they can reveal where people genuinely want or need to walk.

Urban planners often design pathways based on symmetry, appearance or traffic rules. But the researchers argue that cities function better when they reflect natural human behaviour.

The findings could help planners build more practical sidewalks, improve park layouts and create transport systems that people actually use the way they are intended.

The researchers believe energy-based planning could also improve accessibility around shopping centres, parking areas and public transport hubs.

In the end, those muddy shortcuts across city lawns may represent something far more intelligent than carelessness. They are the visible signs of thousands of everyday decisions made by people simply trying to move through the city in the easiest possible way.