A neighbourhood is not encountered all at once. Its environmental qualities arrive through a sequence of turns, delays, openings, remembered corners, familiar shortcuts and interruptions whose effects cannot be inferred from the plan alone. A green surface recorded by a satellite may indicate vegetation without telling us whether the pedestrian sees it, can enter it, wants to remain there, or feels entitled to occupy it. A high score for walkability may describe connected streets without specifying whether the person crossing them is rested, apprehensive, hurried, physically constrained or searching for company. The tension is not between objective knowledge and subjective opinion, as though the researcher merely had to choose a side. It is between different operations for making a neighbourhood knowable, each capable of disclosing something that another necessarily omits. Dadvand and colleagues' school-based epidemiology demonstrates why spatial exposure must extend beyond the dwelling: the child's passage between home and school is itself a meaningful environmental interval, and cognitive development must be examined across time rather than extracted from one isolated observation. Yet an index of greenness, however finely resolved, cannot reveal the affective or biographical character of that passage. Bornioli, Parkhurst and Morgan begin from the other direction. Through photo-elicitation they give participants a means to identify places whose psychological significance arises during walking, including experiences that a standard spatial inventory would not have anticipated. The resulting evidence is richer in meaning but does not establish the same claims about population health. These are not rival methods waiting to be reconciled into a single superior score. They are instruments whose productive differences should be preserved. Hartig and colleagues complicate matters further by showing that environmental restoration has a trajectory: physiological response, attention and affect may change during and after an encounter, and their movements need not coincide. A walk is therefore neither a fixed dose nor a timeless experience. It has a before, a during and an after, and the need for restoration can be shaped by what happened before the first step. Korpela and colleagues locate this sequence inside a longer personal geography. A favourite place is not restorative simply because it possesses a prescribed set of natural features; its significance also depends on repeated use, remembered experience, stress, social relations and the individual's history of seeking relief. The same park may be a refuge, a compulsory passage, a site of labour, or an inaccessible promise. These differences cannot be read from the park's polygon. White and colleagues' large-scale analysis of time in nature makes a parallel distinction visible at another scale. Their association between weekly nature contact and health or wellbeing is important precisely because it shifts attention from proximity to actual time spent, but duration alone cannot tell us what that time contained. A person with abundant free time and another who must compress movement between obligations may report equal minutes while inhabiting radically different conditions of choice. The methodological problem is thus one of non-equivalence: mapped opportunity, actual passage, remembered attachment, measured response and accumulated contact all describe real dimensions of the urban environment, but none can legitimately substitute for all the others. The most consequential evidence may appear at their points of disagreement. A route classified as environmentally advantageous may produce fatigue or fear; a modest, heavily built street may sustain attachment and social reassurance; a short passage may provide a stronger sense of agency than a longer, greener alternative. Such contradictions are not noise to be removed by averaging. They are clues to how a place acquires capacity through relations among bodies, infrastructures, histories and practices. Kołodyńska, Rinne and Kyttä make this point spatially through the difference between necessary and optional activities in suburban Poland. Their participatory mapping discloses the geography of obligation and possibility: journeys made because daily life requires them do not occupy the same experiential category as journeys chosen for pleasure. The distinction also questions a common planning reflex. Connectivity is not automatically autonomy; access to a destination does not establish freedom over the journey; and a landscape capable of supporting optional activity does not guarantee that everyone can use it. The neighbourhood must therefore be understood as a differentiated field of potential actions whose value is realised, frustrated or transformed through situated movement. It is not simply an object awaiting measurement but a changing relation between what is materially offered, what is socially permitted, what is physically possible and what becomes meaningful to the person moving through it.
The methodological consequence is to construct a research archive in which these differences remain retrievable rather than being flattened into a composite neighbourhood score. The route should function as an evidentiary sequence: an ordered set of observations, decisions, interruptions, transitions and interpretations, connected to environmental measurements without being absorbed by them. This requires more than adding a qualitative comment field to a geographic information system. It means deciding what the smallest comparable unit of evidence can be, what contextual information must accompany it, and which forms of uncertainty deserve to survive the act of classification. A route's coordinates may be stored as a spatial trace; its circumstances may include time, weather, traffic, social company, bodily effort, purpose and the participant's freedom to deviate. But a trace is not a complete account of experience, and a statement of feeling is not a complete account of exposure. Their relationship must be recorded as a relationship. Kahila-Tani's work on participatory GIS shows why this is simultaneously an epistemological and an institutional problem. Once a personal experience becomes a point or line on a planning map, it gains visibility, portability and apparent comparability. It can travel into a meeting, be grouped with other observations and appear as evidence in a decision. Yet the same conversion can detach the mark from the narrative that gave it significance. The map is not simply an innocent container for local knowledge. It is an interface that decides what becomes countable, which differences can be represented, and how much interpretation is left to the person who originally supplied the information. An accountable walking archive would therefore preserve provenance: who made an observation, under what conditions, with what degree of confidence, and how it was subsequently interpreted or aggregated. It would distinguish participant-chosen routes from researcher-designed comparison routes, and separate what was observed directly from what was inferred from external spatial datasets. It would also allow contradictions to be found again. When objective accessibility and experienced accessibility diverge, the system should not silently resolve the conflict in favour of the supposedly more rigorous layer. It should permit the disagreement to become a research question. Such a structure changes the status of metadata. Metadata is no longer administrative residue attached after fieldwork; it is the means by which situated evidence retains its conditions of production across places, observers and time. The choice of which categories to standardise and which to leave open is correspondingly political. Too little structure makes cross-city comparison weak; too much structure erases the very differences that walking research was designed to reveal. Kitchin's engagement with distant time sharpens this dilemma by insisting that urban conditions are not merely distributed across space but organised through temporal power. Waiting at a crossing, navigating an unfinished redevelopment, taking a detour around a construction site or encountering a place whose future has already been decided elsewhere are not trivial deviations from an ideal pedestrian itinerary. They are experiences of governance materialised as movement. The archive must therefore be capable of registering infrastructural and political time alongside individual duration. It must ask who controls the pace of change, who absorbs its friction, and whose remembered landscape is treated as disposable when a new plan becomes authoritative. This is particularly important when longitudinal comparison is attempted. Returning to a route does not reproduce the earlier walk; it establishes a new observation in relation to a previous configuration of place, body, expectation and institution. The temporal comparison must retain both continuity and difference, rather than projecting a false stability onto the same coordinates. Health evidence adds another responsibility. Associations between environmental exposure and wellbeing can inform planning, but they should not be used to turn individual reports into diagnoses or to infer clinical benefit from a single pleasant walk. Likewise, detailed GPS traces can expose home locations, routines and vulnerable patterns of movement. The possibility of producing precise data does not automatically confer a right to publish them. Spatial masking, selective access and careful separation of identifying traces from shareable analytical descriptions are part of the knowledge architecture, not external restrictions imposed upon it. The strongest public result may sometimes be an aggregate pattern whose individual paths remain deliberately opaque. A comparative instrument built on these principles would make available a more demanding form of urban evidence: one in which exposure, restoration, obligation, choice, attachment and governance can be examined together without being declared equivalent. It would make neighbourhood capacity legible as a profile of situated possibilities, not as a single promise of wellbeing. In Socioplastics, the resulting tension between trace, interpretation and public evidence condenses as Relational Agency.
