Map key Overview map Route summary table Introduction Geology Brief history Getting to Corsica Getting around Corsica Getting to the GR20 When to trek How to trek Maps Mountain weather Path conditions Mountain rescue What to take Services along the route Food, drink and fuel Language Currency Using this guide Plants and wildlife on Corsica Maquis Trees Flowers Wildlife The GR20 Stage 1A Calinzana to Refuge d and #039;Ortu di u Piobbu (high-level) Stage 1B Calinzana to Refuge d and #039;Ortu di u Piobbu (low-level) Excursion Ascent of Monte Corona from Refuge d and #039;Ortu di u Piobbu Stage 2A Refuge d and #039;Ortu di u Piobbu to Refuge de Carozzu (high-level) Stage 2B Refuge d and #039;Ortu di u Piobbu to Refuge de Carozzu (low-level) Stage 3 Refuge de Carozzu to Ascu Stagnu Stage 4 Ascu Stagnu to Auberge U Vallone Link route Auberge U Vallone to Albertacce Stage 5 Auberge U Vallone to H and amp;ocirc;tel Castel di Vergio Excursion Ascent of Paglia Orba from Refuge de Ciotullu di I Mori Stage 6 H and amp;ocirc;tel Castel di Vergio to Refuge de Manganu Link route Bergerie de Vaccaghja to Corti Link route Refuge de Manganu to Soccia Stage 7 Refuge de Manganu to Refuge de Petra Piana Link route Br and amp;##xe8;che de Capitellu or Bocca a Soglia to Bergeries de Grottelle Excursion Ascent of Monte Ritondu from Refuge de Petra Piana Stage 8A Refuge de Petra Piana to Refuge de l and #039;Onda (low-level) Stage 8B Refuge de Petra Piana to Refuge de l and #039;Onda (high-level) Link route Bergerie de Tolla to Tattone and Vizzavona Stage 9A Refuge de l and #039;Onda to Vizzavona (low-level) Stage 9B Refuge de l and #039;Onda to Vizzavona (high-level) Stage 10 Vizzavona to Bergeries d and #039;E Capanelle Link route La Foce to Bocca Palmentu Stage 11A Bergeries d and #039;E Capanelle to Bocca di Verdi (low-level) Stage 11B Bergeries d and #039;E Capanelle to Bocca di Verdi (high-level) Stage 12 Bocca di Verdi to Refuge d and #039;Usciolu Link route Refuge d and #039;Usciolu to Cuzz and amp;##xe0; Stage 13 Refuge d and #039;Usciolu to Refuge de Matalza Link route Tignosellu to Zicavu Link route Zicavu to Refuge de Matalza Stage 14 Refuge de Matalza to Refuge d and #039;Asinau Alt Stage 13/14 Refuge d and #039;Usciolu to Refuge d and #039;Asinau (variant) Stage 15A Refuge d and #039;Asinau to Bavedda (low-level) Stage 15B Refuge d and #039;Asinau to Bavedda (high-level) Stage 16 Bavedda to Conca Appendix A Facilities along the route (Calinzana to Conca) Appendix B Facilities along the route (Conca to Calinzana) Appendix C Accommodation list Appendix D Basic language notes Appendix E Useful contacts Appendix F The Cirque de la Solitude.