Cristina, a German assistant we have, came today and told us about the Berlin Wall.
She said that people from both sides: capitalist and communist, went to each other's part to get cheaper food and products and to see inventions which they hadn't. That caused the URSS to make a blockade to stop products from going from one part to another. But people were having tough times, and that didn't help because people from the East (communist) moved to the West (capitalist), escaping to a richer part. So the URSS built the Wall instantly, so that people got separated and couldn't cross because it was very secure and they couldn't jump. Whenever people detected someone crossing, they told the URSS about it, although they were neighbours, friends or even school children.