I had never heard of the Mapparium until I was in Boston and a friend read about it. We checked it out and found it so amazing. It is a globe of the world and is made up of glass bricks. The original idea was to constantly update the countries but they soon realised that with the way borders etc change this would be too time consuming and costly and so it is as it was in the 1930's. you walk into the inside of the globe onto a glass walkway so that you can see the whole world and then you listen to an audio. If you stand at one end of the walkway and whisper, the person at the other end can hear it clearly. When we look at a globe from the outside we can only see part of the world at one time but by being in the interior you can see the whole thing - amazing.