I occasionally check what map sites have on the most secretive installtion within walking distance of me, a huge data centre that used to have a sign on the gate saying the Royal Bank of Scotland owned it and is now completely unidentified. It's south of Edinburgh on the corner of the B6392 and Melville Gate Road

All the map sites agree on the size of the thing, but Google is consistently less up to date and lower resolution than Apple or Bing. You can see exactly how many air conditioning vents there are on the better images, and more of the elaborate precautions against somebody driving a suicide truck bomb into it. Why the discrepancy? No idea. You'd think if they were really determined to hide the thing from attackers, all the map sites would show it as a potato field or caravan park.