  The random walk with hyperbolic probabilities that we are introducing is an
example of stochastic diffusion in a one-dimensional heterogeneous media.
Although driven by site-dependent one-step transition probabilities, the
process retains some of the features of a simple random walk, shows other
traits that one would associate with a biased random walk and, at the same
time, presents new properties not related with either of them. In particular,
we show how the system is not fully ergodic, as not every statistic can be
estimated from a single realization of the process. We further give a geometric
interpretation for the origin of these irregular transition probabilities.
