mapview

    if (self.isBeingPresented) {

        //set the map delegate
        MapView.delegate = self;

    //set the co-ords
    CLLocationCoordinate2D zoomLocation;
    zoomLocation.latitude = LAT_POSN;
    zoomLocation.longitude= LON_POSN;

    //create region
    MKCoordinateRegion viewRegion = MKCoordinateRegionMakeWithDistance(zoomLocation, startZoom, startZoom);
    MKCoordinateRegion adjustedRegion = [MapView regionThatFits:viewRegion];
    [MapView setRegion:adjustedRegion animated:YES];

        //create a new insatnce of the map overlay object
        MapOverlay * mapOverlay = [[MapOverlay alloc] init];
        //added the over lay
        [MapView addOverlay:mapOverlay];


    }