Techniques for providing driving instructions for drivers on unfamiliar roads. A navigation system (110) stores "breadcrumbs," or indicators of road segments on which a particular vehicle has previously driven. The system detects whether a vehicle has turned off of a "familiar" road by examining these breadcrumbs. If the navigation system determines that the current position of the vehicle is associated with a road segment for which a number of breadcrumbs below a particular threshold are stored, then the navigation system determines that the vehicle is on an unfamiliar road. The navigation system identifies a secondary path and presents that path to the driver to return the driver to the familiar road. The secondary path may be identified in a manner that avoids obstacles by examining traffic information or distance information.
展开▼
