I do often rely on my sat nav when I am in unfamiliar territory but am always surprised to read stories like this. It seems some people blindly follow the directions rather than using a little bit of common sense and looking at their surroundings and road signs. In this extreme example a Belgian woman ended up driving 900 miles after she followed a broken sat nav. She originally set out on what should have been a 38 mile journey to pick up a friend from the train station.
Taking a wrong turn she drove 900 miles and ended up in Zagreb in Croatia. She crossed five borders and would have seen road signs in several different languages but failed to notice the mistake. This was despite having to stop several times to refuel her car and stopping for a roadside nap. She admitted to being distracted during the journey and so continued with the drive only noticing the error when she got to Zagreb and found she was no longer in Belgium.