 
 public class MapboxStaticMap {
 
-    let requestURLStringBase = "https://api.tiles.mapbox.com/v4/"
+    private let requestURLStringBase = "https://api.tiles.mapbox.com/v4/"
 
     public enum ImageFormat: String {
         case PNG    = "png"

        case JPEG70 = "jpg70"
    }

    public var requestURL: NSURL

    public lazy var image: UIImage? = {
        if let data = NSData(contentsOfURL: self.requestURL) {


    public class Overlay {

        private(set) var requestString: String = ""

    }

