So far we've visited 54 out of 936 sites included in the famous UNESCO World Heritage List. Still plenty left to see, but it's a good start. From our experience, despite the glory and fame a place should gain from being on this list, some sites just don't get lucky with tourist (the Palace and Park of Fontainebleau was deserted when we visited in mid July) and others, despite their historical and cultural value, are just not much to see (the Archivo de Indias in Seville is a boring place filled with archival documents illustrating the history of the Spanish Empire in the Americas and the Philippines). But in general the sites listed in the UNESCO World Heritage List are breathtaking and worth a visit, so it's safe to join the crowds.
Austria
Historic Centre of Salzburg
Palace and Gardens of Schönbrunn
Historic Centre of Vienna
Belgium
La Grand-Place, Brussels
Historic Centre of Brugge
Czech Republic
Historic Centre of Prague
France
Palace and Park of Versailles
Banks of the Seine, Paris
Palace and Park of Fontainebleau
The Loire Valley between Sully-sur-Loire and Chalonnes
Historic Site of Lyons
Germany
Hanseatic City of Lübeck
Palaces and Parks of Potsdam and Berlin
Cologne Cathedral
Museum Island, Berlin
Upper Middle Rhine Valley
Vatican City
Hungary
Budapest, the Banks of the Danube, the Buda Castle Quarter and Andrássy Avenue
Italy
Church and Dominican Convent of Santa Maria delle Grazie
Historic Centre of Florence
Historic Centre of Rome
Piazza del Duomo, Pisa
Venice and its Lagoon
Historic Centre of Naples
Archaeological Area of Pompei
Assisi and the Basilica of San Francesco
City of Verona
Netherlands
Seventeenth-century canal ring area of Amsterdam
Portugal
Historic Centre of Porto
Monastery of Batalha
Monastery of the Hieronymites and Tower of Belém in Lisbon
Monastery of Alcobaça
Cultural Landscape of Sintra
Romania
Churches of Moldavia
Spain
Alhambra, Generalife and Albayzín, Granada
Historic Centre of Cordoba
Monastery and Site of the Escurial, Madrid
Works of Antoni Gaudí
Old Town of Ávila
Old Town of Segovia and its Aqueduct
Historic City of Toledo
Mudejar Architecture of Aragon
Cathedral, Alcázar and Archivo de Indias in Seville
Old City of Salamanca
La Lonja de la Seda de Valencia
Palau de la Música Catalana and Hospital de Sant Pau, Barcelona
University and Historic Precinct of Alcalá de Henares
Palmeral of Elche
Switzerland
Old City of Berne
UK
Stonehenge
Blenheim Palace
City of Bath
Westminster Palace, Westminster Abbey and Saint Margaret's Church
Tower of London