The Who have a reputation as a wildly unpredictable and improvisational rock quartet, but these days they tour as an eight-piece ensemble offering classic hits. Bob Dylan performs swing and jazz covers made famous by Frank Sinatra.
These are some of the most important rock stars of the last 50 years, who have had some of the greatest recordings and performances ever. And they have never all appeared together.
For older fans, it will seem like a coming together of the gods. For younger fans (under 70) it will be a chance to witness the originators of modern pop culture before they shuffle off the stage. But what does it say about modern music and culture?
Woodstock was also a protest against war, capitalism and convention. A symbol of the 60s ethos of "peace and love". So many people turned up they let them in for free. The 400,000-strong crowd was known for drugs, nudity and fierce idealism.
The festival was also a muddy shambles. Many of the acts were the worse for wear for drugs and alcohol.
This year's mega festival will feature no such amateurism - and is very unlikely to be free.
- The Sunday Telegraph