Follow the below code to set region from CLLocation array
Here routess is an array containing CLLocation.

-(void) setRegionForMap {

    MKCoordinateRegion region;

    CLLocationDegrees maxLat = -90;
    CLLocationDegrees maxLon = -180;
    CLLocationDegrees minLat = 90;
    CLLocationDegrees minLon = 180;
    for(int idx = 0; idx < routess.count; idx++)
    {
        CLLocation* currentLocation = [routess objectAtIndex:idx];
        if(currentLocation.coordinate.latitude > maxLat)
            maxLat = currentLocation.coordinate.latitude;
        if(currentLocation.coordinate.latitude < minLat)
            minLat = currentLocation.coordinate.latitude;
        if(currentLocation.coordinate.longitude > maxLon)
            maxLon = currentLocation.coordinate.longitude;
        if(currentLocation.coordinate.longitude < minLon)
            minLon = currentLocation.coordinate.longitude;
    }
    region.center.latitude     = (maxLat + minLat) / 2;
    region.center.longitude    = (maxLon + minLon) / 2;
    region.span.latitudeDelta  = maxLat - minLat + 0.5;
    region.span.longitudeDelta = maxLon - minLon + 0.5;


    if (region.center.latitude != 0 && region.center.longitude != 0) {


        [mapViewUsers setRegion:region animated:YES];

    } else
    // set the current location region
    }    
}