The GR20 is one of the great walks of Europe, comparable in length to the Tour of Mont Blanc and similar in quality to the Cuillen Ridge on Skye. It runs across Corsica northwest to southeast. It crosses jagged peaks, that are snow covered for much of the year. It is over a hundred and thirty miles long, involves over 25,000 metres of ascent and descent and takes nearly two weeks. It is divided into two sections by a small gauge railway that crosses the GR20 at Vizzavona. We walked the northern part from Calenza in 2001 and the southern part from Conca in 2004, when we had just turned sixty. Like so many who do this walk, we found our own way, carrying all our food and the minimum of gear and clothing. This is an account of the walk, plus excursions to the Aiguilles de Bavella and Monte Renosu, two high level variants. It will introduce you to the joys of multi-day high level walking and maybe encourage you to try for yourselves.