Cognitive Aspects: How People Perceive, Memorize, Think and Talk About Landmarks - Landmarks: GIScience for Intelligent Services - page 57

the air travel network. People experience them mostly from the inside, where they
more often than not look interchangeable. For example, Singapore Changi Airport
is a node in this network experienced by millions of travelers per month. A travel
agent telling her customer “At Changi, change to the flight to Frankfurt” may help
with orientation and wayfinding. But usually it does not evoke or relate to the visual
image of the terminal buildings. Train stations have a similar prominence in spite of
low visual imaginability.
Similarly, other categories of objects or events can have this landmarkness.
For example, in natural environments a prominent representative for landmarks is
landform. Prototype landform objects are mountains, saddles or rivers, which all
can be characterized by their visual, semantic or structural qualities. Mathematically
they form singularities in the terrain height. Even slope alone is already observed
as a peculiarity in learning, memorizing and communicating environments and
routes. In orienteering a route description can be: “Walk uphill”. The salience of
slope is visual as well as structural (in terms of resistance, or increased physical
effort to overcome this part of the route). In Lynch's categorization slope would
form a gradual, but conquerable barrier. However, little literature exists on natural
landmarks. For example, Brosset et al. report that landform is the second largest
category of landmarks in route directions in natural environments [ 15 ] . In urban
environments landform has not been systematically investigated. This may be
caused by the availability of local, fine-grained objects to choose from (landform
is of comparably coarse grain), or also by the fact that salient patterns of landform
(e.g., steep slopes) are relatively rare in urban environments.
For urban environments Ishikawa and Nakamura have tested which categories of
objects people use as landmarks [ 88 ] , however in a narrow context. In their experi-
ment people walked unfamiliar routes in an urban environment, and were asked to
nominate the “objects that they thought were helpful as clues for navigation”, or
more precisely, “to imagine a situation where they use those landmarks to explain
the routes to someone who visited the place for the first time” (p. 8). Participants
were also asked to give reasons for their selections. Despite this narrow context,
Ishikawa and Nakamura could show that people picked various objects such as
buildings, signage, street furniture or trees. Also, since this was a reporting task
to an experimenter, not an instruction task to a wayfinder, participants with a better
sense of direction tended to select fewer landmarks. They also studied the physical
properties of selected buildings, finding that facade area, color saturation, and age
affected the selection, but that these parameters can differ between persons and
routes. Denis et al. [ 40 ] also looked at object categories in verbal route descriptions
of residents of Venice. They found that streets, bridges and squares were mentioned
far more frequently than buildings. Lynch's collected sketches of some North
American cities [ 128 ] would allow a similar quantitative analysis, which has not
been done yet.
However, in each of these studies the environment itself (such as Venice with its
bridges) as well as the assumed activity or purpose provide a specific context. Both
context factors, environment and activity or purpose, influence the choice of object