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Today, anyone feeling lost in a city or unsure about how to navigate can use navigation services to look up routes to where they want to go. Current research investigating these services has primarily focused on how to find an appropriate route and how to best support navigation along it, and not how routes and the maps they are presented on are perceived. What makes one route look more difficult to navigate than another? And how does experience with using navigation services and maps in daily life influence how difficult a route is perceived to be? We explored these questions in a survey study where participants rated the perceived difficulty of pedestrian routes in ten different cities. The results show that routes in more complex urban environments were perceived as more complex than routes in easier environments. At least partly, perceived difficulty seems to follow earlier conceptualizations of route complexity, but open questions remain regarding the interplay of environmental structure, route properties, and the map representation.

The routes displayed on maps by navigation support systems are intended to help users to orient themselves towards reaching the destination and to infer information related to their navigation. Inferring how complex a route is, including how well you think you can remember it and the likelihood of getting lost, may influence expectations on how it is navigated. However, it is not well understood when and where a route displayed on a map is perceived as complex and why someone perceives it this way. Current methods for assessing complexity tend to focus either on (i) the complexity of the route or on (ii) the complexity of the environment as a static and global property. By taking inspiration from navigational map reading and how routes and street networks are perceived on a map, this paper investigates how environmental complexity influences route complexity and length.We developed a new approach to gauge the alignment between the orientation of a route’s origin and destination with respect to the orientation of the streets within the network, and we investigated how this measure relates to route complexity and length.

How an origin and a destination align with the street network may, anecdotally, be used as a heuristic to infer the length and complexity of routes from the origin to the destination. However, no method of measuring alignment with a street network exists, and furthermore, it is unclear whether and under what circumstances it is useful as a heuristic. In this paper, we propose a novel method for measuring alignment using the Earth Mover's Distance (EMD) between orientation distributions. We evaluated this metric using a dataset of 77,293 origin and destination pairs from 100 cities with different street networks, in order to test the hypothesis that an increasing degree of misalignment is predictive of a longer and more complex route from origin to destination. Our evaluation shows that our method for measuring alignment becomes more useful as a heuristic the more grid-like the street network surrounding the origin and destination is. To conclude, the results obtained indicate that alignment is an important factor for route properties, especially in grid-like street networks, a subclass of routes within an environment where the configuration of the street network makes predicting the length and complexity easier.

Montello’s research on navigation sheds light on the spatial cognition it involves. Earlier research examines how different factors influence route difficulty, analyzing how efficiently navigators  navigate a route and how they experience it. However, navigation also encompasses wayfinding activities before locomotion, e.g., when looking at a route suggestion displayed on a map. We explore route difficulty from this perspective by showing route suggestions to participants and asking them to rate how difficult they appear to be, examining the impact of factors associated with the difficulty of navigating a route. Results indicate that the number of turns influences the perceived difficulty of a route, while other factors seem not to.

Route suggestions displayed on maps allow users to form an impression of how difficult a route may be to navigate before travel begins. Previous research has extensively examined factors that influence the difficulty of following a route. However, there is very little research on how navigators perceive route difficulty from a map representation alone. This study investigates what people describe as making routes appear difficult to navigate and explores how this might be assessed computationally. Participants evaluated the perceived difficulty of 18 pedestrian routes shown on maps and provided written explanations of their judgments. A thematic analysis of these responses identified four overarching themes of perceived route difficulty. Participants most frequently emphasized the number and nature of turns, including difficult-to-remember turns. They also referred to the overall shape of the route, particularly its length, straightness, and apparent logic. Additional themes include the structure of the street network, such as intersections, road hierarchy, and street geometry, as well as environmental characteristics including landmarks, similarity of surroundings, or potential traffic. Our findings reveal that perceived route difficulty reflects both properties of the route itself and broader characteristics of the surrounding environment. We discuss how these themes relate to existing measures of route and environmental complexity and identify computational methods that may be used to assess perceived difficulty. The results contribute to a better understanding of how people evaluate route suggestions. They also offer potential for the design of adaptive navigation support systems.