On 16 and 17 August 1987 people gathered at places they held to be sacred, in numbers reported in the tens of thousands worldwide, to meditate at coordinated times. Mount Shasta and Sedona drew large crowds in the United States, and gatherings were reported at Glastonbury, at Machu Picchu, at the Egyptian pyramids and at many smaller sites. The organiser, Jose Arguelles, presented the dates as a turning point at which a sufficient number of people acting together could shift the direction of human affairs.
Wouter Hanegraaff's study of New Age religion is the standard scholarly treatment of the wider movement, and what the Harmonic Convergence supplies is the moment at which a diffuse network of practices, bookshops, workshops and small groups did something simultaneous and public and was therefore noticed. Before it, the New Age was largely invisible to general media; after it, the label was in common use. The atlas records the event as a modern religious gathering of documented scale. It is included on exactly the same footing as older events, because the atlas covers new and old religion equally and does not treat recency as a reason to leave something out. A gathering of tens of thousands of people at named sites on a named date is exactly the kind of event a religious atlas exists to record, whatever anyone makes of the reasoning behind it.
Sources New Age Religion and Western Culture: Esotericism in the Mirror of Secular ThoughtWouter J. Hanegraaff with The Mayan Factor: Path Beyond TechnologyJose Arguelles