This paper outlines the formal representation of the environment in which it
is assumed that a wayfinding process has been occurred through a street
network. Wayfinding is a process in which people navigate themselves from an
origin to a destination by their common sense geospatial knowledge. Na\"ive
Geography is a field of study that investigates the body of knowledge that
people have about the surrounding geospatial world and it deals with common
sense knowledge of space. The image schemas which are needed for wayfinding
with boundary relations method have been extracted and represented formally
with algebraic specifications. These specifications are mentioned in the syntax
of a functional programming language, Haskell. It allows us to execute written
algebraic specifications and provide conditions for rapid prototyping and
formal checks on consistency. These formal specifications are implemented for
modeling street network of a part of Tehran, Capital city of Iran.