In 1969, Woodstock reaped what Monterey sowed. The masses of Baby Boomers who swarmed Yasgur's farm that weekend may have called themselves "freaks" or “heads,” instead of hippies, but the festival's animating spirit was pure Flower Power, straight out of the Haight. Almost by accident, Woodstock evolved over those three famous days from a rock festival into a kind of public art project, an experiment in alternative community that demonstrated, however briefly, the possibility of organizing a society around values diametrically opposed to those of corporate capitalist America. On camera at least, Woodstock made that new society look like heaven. Less than four months later, the Rolling Stones' disastrous festival at Altamont made it look like hell.

Corporate capitalism, though, has never met a menace it couldn't co-opt and exploit, and there was clearly big money in big concerts. Huge festivals, sans the utopian fantasies, continued into the 1970s. In 1973, the single-day Summer Jam at Watkins Glen drew a record-setting 600,000 fans to hear and see, sort of, the Allman Brothers, The Band, and Grateful Dead. In 1974, the Ozark Music Festival, featuring The Eagles, Blue Öyster Cult, Lynyrd Skynyrd, and a rumored Beatles' reunion, drew an estimated 350,000 for a chaotic mid-Missouri weekend. (The Beatles, in case you were wondering, didn't show up.)

But the dozens of giant, music festivals we know today, like the Jambaloosa in Pittsburgh and Some Kind of Jam in Kempton, Pennsylvania, took a few more decades to appear. For that, and for creating a second, and even a third generation of hippie, we can thank, and/or blame, the Grateful Dead.

The house band for the Haight never stopped touring throughout the '70s and '80s, fostering a huge community of supremely devoted fans. For an astounding seven straight years from 1988 to 1995, according to Pollstar's Top Tours, the Grateful Dead never left the top-five grossing acts in North America. In the fields and parking lots around the venues, though, they did something even more remarkable. The Dead were less a band than a Flower Power version of a tent show revival, winning converts to the hippie faith. A huge traveling city grew up around them—with an equally huge underground economy based solely on love, music, tie-dye shirts, friendship bracelets, and, oh yeah, millions and millions of hits of LSD.

Unlike the band, however, most of the Deadheads dropping acid in the Clinton era didn't remember Monterey—because they hadn't been alive for it. The hippies filling stadiums for Dead shows in the ‘90s were a new breed, a second generation. They were Gen-Xers who donned their elders' garb, but tended to ascribe a different meaning to it. They had to. The political and social connotations of hippiedom that were radical in the 1960s, like, say, a man having long hair, or an unmarried couple living under the same roof, had become mainstream by the 1990s, and the second generation of hippies didn't have as many cultural battles to fight. Where the Boomers had a sex, drugs, and rock and roll revolution, Gen X grew up in the messy blowback of AIDS, crack and MTV, and the Gen X hippie tended to be much less interested than their predecessors in trying to change the world and more about creating worlds of their own.