Three medieval fortresses in southern Switzerland are expected to be declared sites of "outstanding universal value", when the United Nations' World Heritage Committee meets in Australia from November 27 to December 2.
The castles in the town of Bellinzona are among 71 natural and cultural sites nominated for inclusion on Unesco's World Heritage List, which includes 630 sites worldwide.
The Swiss site has good chances of being added to the list, after obtaining a recommendation at a preparatory meeting in June.
If accepted, it would bring to four the number of World Heritage sites in Switzerland. The others, all included in 1983, are the Old City of Bern, the Convent of St Gallen, and the Benedictine Convent of St John at Müstair.
Despite Switzerland's fame as a country of outstanding natural beauty, not one of these is a natural site. An application to place Europe's longest glacier, the Aletsch, on the World Heritage List will be considered next year.
In the reports on this special site, swissinfo has taken a detailed look at what makes the three existing Swiss World Heritage sites and the two applicants so special.
The World Heritage List was established under the terms of a convention on protecting the world's natural and cultural heritage, which was adopted by Unesco's member states in 1972. More than 160 countries have signed the convention.
To be included, sites must be of outstanding universal value, a definition which leaves the World Heritage Committee with considerable room for manoeuvre.
In practice, a cultural site may be added if it is considered to be a masterpiece of creative genius, to have exerted great architectural influence, is associated with beliefs of universal significance or is an outstanding example of a particular way of life.
Natural sites must exemplify major stages in the earth's history, contain natural habitats of endangered creatures, or simply be a scene of exceptional beauty.
Inclusion on the list can be an asset for tourism, but it also commits countries to protecting their heritage.
by Malcolm Shearmur