var opt = {
  lat:39.264502,
  lng:-5.995333,
  z:7,
  basemap:5,
  overlay:1
};

var BASEOVERLAYS = [ 
  null, // Please leave this line alone :)
  
  [ // Base 1 : Google Normal Map  
    1, // Political
    // 2, // Roadmap (Google Normal Map is showing the roads, so we won't need the roadmap overlay)
    3, // Map Grids
    4 //  Natural Parks !!! don't forget to remove the comma after the number 4, because we comment 
      //  the other lines and this one is being the last number on this array.
    // 5, // Roadmap + Political Layer
    // 6, // Natural Parks + Roadmap
    // 7  // Roadmap + Map Grids
  ],
  [ // Base 2 : Google's Satellite Map
    1, // Political
    2, // Roadmap
    3, // Map Grids
    4, // Natural Parks
    5, // Roadmap + Political Layer
    6, // Natural Parks + Roadmap
    7  // Roadmap + Map Grids  
  ],
  [ // Base 3 : Google's Terrain Map
    1, // Political
    2, // Roadmap
    3, // Map Grids
    4, // Natural Parks
    5, // Roadmap + Political Layer
    6, // Natural Parks + Roadmap
    7  // Roadmap + Map Grids  
  ],
  [ // Base 4 : Natural 
    1, // Political
    2, // Roadmap
    3, // Map Grids
    4, // Natural Parks
    5, // Roadmap + Political Layer
    6, // Natural Parks + Roadmap
    7  // Roadmap + Map Grids  
  ],
  [ // Base 5 : Contours
    1, // Political
    2, // Roadmap
    3, // Map Grids
    4, // Natural Parks
    5, // Roadmap + Political Layer
    6, // Natural Parks + Roadmap
    7  // Roadmap + Map Grids  
  ]
];