Visit 50 of the world heritage sites

As of March 2007, I have visited (in chronological order) the following UNESCO WHSs:
1980> Independence Hall, Philadelphia, Pennsylvania USA
1983> Paris, Banks of the Seine, France
1983> Palace and Park of Versailles, France
1983> Strasbourg – Grande île, France
1984> Tower of London, England, UK
1984> Westminster Palace, Westminster Abbey and Saint Margaret’s
Church, England, UK
1987> Monticello and the University of Virginia in Charlottesville, USA
> Historic Center of Puebla, Mexico
> Cape Floral Region Protected Areas, South Africa
> Pre-Hispanic City of Teotihuacan, Mexico
> Tiwanaku: Spiritual and Political Centre of the Tiwanaku Culture, Bolivia
> Colonial City of Santo Domingo, Dominican Republic
> City of Quito, Ecuador
> Monastery of the Hieronymites and Tower of Belém in Lisbon, Portugal
> Cultural Landscape of Sintra, Portugal