In reply to happymarmot:
Some excellent ones in Italy:
- Alta Via of the Aosta Valley
http://www.lovevda.it/turismo/proposte/sport/escursionismo/alta_via_1_e.asp
http://www.lovevda.it/turismo/proposte/sport/escursionismo/alta_via_2_e.asp...
Very well signposted and documented, beautiful, great food and wine...
- Sentiero Roma
http://www.paesidivaltellina.it/sentieroroma/index.htm
very demanding, very alpine, takes you across the south side of the Badile range in 5 stages, can be combined with the following:
- Alta via of the Malenco Valley
http://www.sondrioevalmalenco.it/03_escursioni/01_altavia.html very dramatic takes you round the foot of Piz Bernina in 8 stages.
And there are some multi-stage walks in the Dolomites:
http://www.dolomiti-altevie.it/en/Default.aspx?tabid=210
And then there is of course the GTA:
http://books.google.it/books/about/Through_the_Italian_Alps.html?id=mtQNSdQ...
In my alpine experience, Italian refuges are more comfortable and human, and have far better food than their French or Swiss equivalents (I've never been to Austria). Did the Alta Via of the Valle d'Aosta No. 2, which runs through the Gran Paradiso national park 3 years ago. Great experience, hard work though, as you cross from valley to valley each day. Did part of the Alta Via of Valmalenco about 10 years ago. The Marinelli hut is a stunning location.
Have fun!