Taking care of monuments is at the same time taking care of the meanings of buildings in new times. And that's exactly the theme of Open Monument Day 2002: symbols. A lot of buildings stand for something. They noticeably refer to values, contexts, convictions that are per definition invisible or abstract (just think about the twin towers) They do this as a whole - because of their size, height, position, structure - and because of invisible elements in, on or by the building, e.g. Christian, Jewish and Masonic symbols, heraldry, crafts and professions or funeral symbols… The knowledge of this symbolism is often essential in order to ‘read’ the building and to be able to understand its meaning. When this knowledge disappears, symbols threatened to become meaningless and a very interesting language dies. Fully understanding this language is also essential in the care for monuments, e.g. when maintenance and restaurating buildings or in thinking processes about new destinations and unlocking.