Fans of the Grateful Dead are pouring into San Francisco for three days of concerts and festivities marking the 60th anniversary of the scruffy jam band that came to embody a city where people wore flowers in their hair and made love,

Trey Anastasio of Phish, Billy Strings and Sturgill Simpson were among the special guests to join the band over three nights of concert and amid a city-wide celebration.

Ever. Why? Because at this point, 60 years after the Grateful Dead made their mark on this psychedelic town, it's no longer about the band personnel as much as it is all about The Vibe.