ancient castle fort hilltop landmark monument Norman stone berlin building cristal foster germany modern reichstag stair stairs cambridge chapel church door doorway eclisiastical heaven medievil oak religion keep loom looming Norwich pedestrians shadows shop shoppers steps street tower barcelona Catalunya city collserola europe forster sir south Spain sun tibidabo torre attraction bailey bank battlements grass motte mound ruin tourist walls york business business center Gherkin glass mary axe Norman Foster office round shape skyscraper Swiss Re Building windows