The described method and system provide for utilizing portals during GPS navigation to avoid unnecessary off-route notifications and route recalculation in problem areas. The method and system are described in the context of a GPS unit that is part of a telematics unit in a vehicle. If the route calculated by the GPS unit includes certain problem areas such as tunnels and stacked bridges, the GPS unit may utilize portals to process GPS navigation through those areas. When a user enters a portal, normal GPS navigation is suspended and certain features are disabled. For example, the user will not longer receive Turn-by-Turn (TBT) directions, off-route notifications, error notifications, and route recalculation notifications, until the GPS unit determines that the user has arrived at a second portal or until the user manually re-enables those features. The portals should be preferably located at the inlets and outlets to the problem areas. Thus, while the user is in a problem area, errant GPS information may be discarded or ignored, and the provision of unnecessary off-route notifications and route recalculations to the user may be avoided.