If you type "sense of direction women" into Google, the first article which is listed is from the Royal Institute of Navigation. This article begins as follows:
It is a known stereotype that men cannot multi-task and women have no sense of direction ...
Now I am seeking to challenge this stereotype. I am saying that for all practical purposes, men are very good at multi-tasking. No, that's not it. No, what I am saying is that in our day-to-day lives, there is nothing much so very different between men's and women's sense of direction. And the point is easily proved, because I am sure that everyone reading this would be able to point the way to ... I don't know - Edinburgh Castle, let's say, or the airport. (I earlier tested my nine year-old niece's sense of direction, asking her to point which way to her school, and guess what?)
Seemingly, under somewhat extreme and rather unrealistic circumstances, a woman's sense of direction proves to be slightly less reliable than a man's, but it's no big deal as far as I can tell.
Indeed, I noted in an earlier comment:
Women showed greater activity in the left and right pre-frontal regions, while men showed increased levels of activity in the hippocampus.
Further research on my part has shown that actually the hippocampus is larger in women than in men. So, as I also said, whatever differences there are seem to me to be quite academic.
The case is, a sense of direction is innate. This article from Scientific American covers most of the details.
Just as people have a sense of rhythm, or a sense of balance, or a sense of hot and cold, and so on, so people have a sense of direction. Where people genuinely claim to have no sense of direction, it might actually be the case that what they have is a mild form of dyspraxia.
In the hills - or on a mammoth walk with the dog, as I found out not so long back - our sense of direction can end up letting us down. In large part this is because there are no familiar landmarks to help us "stay found", and so we become disorientated.
Okay, now navigation is defined as the process or activity of accurately ascertaining one's position, and planning and following a route.
As we begin to navigate an unfamiliar environment, we depend heavily on landmarks. We look for these and use them to mark our way. As we begin to get more familiar with the environment, we start to remember the routes we take from landmark to landmark, using this to retrace our routes when required. Finally, as we start to gain this knowledge, we use our base of both landmarks and routes to create a cognitive map of the space, so we can make decisions based on spatial differences between landmarks. We can make abstract judgments about the best way to navigate based on the map we have in our heads.
(This "cognitive map" is exactly what chdot was referring to when he talked about the very comprehensive 'map' in his head of Edinburgh's off-road routes.)
The more I think about it, the more convinced I become that for all day-to-day purposes, there is nothing to separate men's and women's sense of direction, or even to the way in which we navigate our way around the place.