If you are already in the region, you will not get notified that you entered a region, because the state hasn't changed.
On iOS 7 and later, you can use -[CLLocationManager requestStateForRegion:]
to request the current state for a region as you start to monitor it. -(void)locationManager:(CLLocationManager *)manager didDetermineState:(CLRegionState)state forRegion:(CLRegion *)region
on your CLLocationManagerDelegate.
If you need to support iOS 6, you can do this manually by checking if the region contains the device's current coordinate, via -[CLRegion containsCoordinate:]